diff --git a/frontend/app/(main)/admin/userMng/rolesList/[id]/page.tsx b/frontend/app/(main)/admin/userMng/rolesList/[id]/page.tsx
index 62d9b3e0..3c3464fb 100644
--- a/frontend/app/(main)/admin/userMng/rolesList/[id]/page.tsx
+++ b/frontend/app/(main)/admin/userMng/rolesList/[id]/page.tsx
@@ -388,9 +388,7 @@ export default function RoleDetailPage({ params }: { params: Promise<{ id: strin
             </Button>
             <div className="flex-1">
               <h1 className="text-3xl font-bold tracking-tight">{roleGroup.authName}</h1>
-              <p className="text-muted-foreground text-sm">
-                {roleGroup.authCode} • {roleGroup.companyCode}
-              </p>
+              <p className="text-muted-foreground text-sm">{roleGroup.authCode}</p>
             </div>
             <span
               className={`rounded-full px-3 py-1 text-sm font-medium ${
diff --git a/frontend/app/(main)/admin/userMng/rolesList/page.tsx b/frontend/app/(main)/admin/userMng/rolesList/page.tsx
index 4b1dbabb..442fc443 100644
--- a/frontend/app/(main)/admin/userMng/rolesList/page.tsx
+++ b/frontend/app/(main)/admin/userMng/rolesList/page.tsx
@@ -2,7 +2,7 @@
 
 import React, { useState, useCallback, useEffect } from "react";
 import { Button } from "@/components/ui/button";
-import { Plus, Edit, Trash2, Users, Menu, Filter, X } from "lucide-react";
+import { Plus, Edit, Trash2, Users, Menu } from "lucide-react";
 import { roleAPI, RoleGroup } from "@/lib/api/role";
 import { useAuth } from "@/hooks/useAuth";
 import { AlertCircle } from "lucide-react";
@@ -10,8 +10,6 @@ import { RoleFormModal } from "@/components/admin/RoleFormModal";
 import { RoleDeleteModal } from "@/components/admin/RoleDeleteModal";
 import { useRouter } from "next/navigation";
 import { useTabStore } from "@/stores/tabStore";
-import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from "@/components/ui/select";
-import { companyAPI } from "@/lib/api/company";
 import { ScrollToTop } from "@/components/common/ScrollToTop";
 import { usePageMultiLang } from "@/hooks/usePageMultiLang";
 
@@ -24,15 +22,12 @@ const LANG_KEYS = [
   "error.occurred",
   "error.close.aria",
   "roles.list.title",
-  "filter.company.placeholder",
-  "filter.company.all",
   "button.create",
   "loading",
   "empty.message",
   "empty.hint",
   "status.active",
   "status.inactive",
-  "label.company",
   "label.memberCount",
   "label.menuPermissions",
   "count.members",
@@ -45,22 +40,19 @@ const LANG_KEYS = [
 
 const DEFAULT_TEXTS: Record<string, string> = {
   "roles.title": "권한 그룹 관리",
-  "roles.description": "회사 내 권한 그룹을 생성하고 멤버를 관리합니다 (회사 관리자 이상)",
+  "roles.description": "권한 그룹을 생성하고 멤버를 관리합니다 (회사 관리자 이상)",
   "access.denied": "접근 권한 없음",
   "access.denied.msg": "권한 그룹 관리는 회사 관리자 이상만 접근할 수 있습니다.",
   "button.back": "뒤로 가기",
   "error.occurred": "오류가 발생했습니다",
   "error.close.aria": "에러 메시지 닫기",
   "roles.list.title": "권한 그룹 목록",
-  "filter.company.placeholder": "회사 선택",
-  "filter.company.all": "전체 회사",
   "button.create": "권한 그룹 생성",
   "loading": "권한 그룹 목록을 불러오는 중...",
   "empty.message": "등록된 권한 그룹이 없습니다.",
   "empty.hint": "권한 그룹을 생성하여 멤버를 관리해보세요.",
   "status.active": "활성",
   "status.inactive": "비활성",
-  "label.company": "회사",
   "label.memberCount": "멤버 수",
   "label.menuPermissions": "메뉴 권한",
   "count.members": "{count}명",
@@ -94,17 +86,12 @@ export default function RolesPage() {
   const isAdmin =
     (currentUser?.companyCode === "*" && currentUser?.userType === "SUPER_ADMIN") ||
     currentUser?.userType === "COMPANY_ADMIN";
-  const isSuperAdmin = currentUser?.companyCode === "*" && currentUser?.userType === "SUPER_ADMIN";
 
   // 상태 관리
   const [roleGroups, setRoleGroups] = useState<RoleGroup[]>([]);
   const [isLoading, setIsLoading] = useState(true);
   const [error, setError] = useState<string | null>(null);
 
-  // 회사 필터 (최고 관리자 전용)
-  const [companies, setCompanies] = useState<Array<{ company_code: string; company_name: string }>>([]);
-  const [selectedCompany, setSelectedCompany] = useState<string>("all");
-
   // 모달 상태
   const [formModal, setFormModal] = useState({
     isOpen: false,
@@ -116,42 +103,18 @@ export default function RolesPage() {
     role: null as RoleGroup | null,
   });
 
-  // 회사 목록 로드 (최고 관리자만)
-  const loadCompanies = useCallback(async () => {
-    if (!isSuperAdmin) return;
-
-    try {
-      const companies = await companyAPI.getList();
-      setCompanies(companies);
-    } catch (error) {
-      console.error("회사 목록 로드 오류:", error);
-    }
-  }, [isSuperAdmin]);
-
-  // 데이터 로드
+  // 데이터 로드 (단일 테넌시: 현재 사용자 회사 기준)
   const loadRoleGroups = useCallback(async () => {
     setIsLoading(true);
     setError(null);
 
     try {
-      // 최고 관리자: selectedCompany에 따라 필터링 (all이면 전체 조회)
-      // 회사 관리자: 자기 회사만 조회
-      const companyFilter =
-        isSuperAdmin && selectedCompany !== "all"
-          ? selectedCompany
-          : isSuperAdmin
-            ? undefined
-            : currentUser?.companyCode;
-
-      console.log("권한 그룹 목록 조회:", { isSuperAdmin, selectedCompany, companyFilter });
-
       const response = await roleAPI.getList({
-        companyCode: companyFilter,
+        companyCode: currentUser?.companyCode,
       });
 
       if (response.success && response.data) {
         setRoleGroups(response.data);
-        console.log("권한 그룹 조회 성공:", response.data.length, "개");
       } else {
         setError(response.message || t("error.load.list"));
       }
@@ -161,18 +124,15 @@ export default function RolesPage() {
     } finally {
       setIsLoading(false);
     }
-  }, [isSuperAdmin, selectedCompany, currentUser?.companyCode]);
+  }, [currentUser?.companyCode, t]);
 
   useEffect(() => {
     if (isAdmin) {
-      if (isSuperAdmin) {
-        loadCompanies(); // 최고 관리자는 회사 목록 먼저 로드
-      }
       loadRoleGroups();
     } else {
       setIsLoading(false);
     }
-  }, [isAdmin, isSuperAdmin, loadRoleGroups, loadCompanies]);
+  }, [isAdmin, loadRoleGroups]);
 
   // 권한 그룹 생성 핸들러
   const handleCreateRole = useCallback(() => {
@@ -271,34 +231,7 @@ export default function RolesPage() {
 
         {/* 액션 버튼 영역 */}
         <div className="flex flex-col gap-4 lg:flex-row lg:items-center lg:justify-between">
-          <div className="flex items-center gap-4">
-            <h2 className="text-xl font-semibold">{t("roles.list.title")} ({roleGroups.length})</h2>
-
-            {/* 최고 관리자 전용: 회사 필터 */}
-            {isSuperAdmin && (
-              <div className="flex items-center gap-2">
-                <Filter className="text-muted-foreground h-4 w-4" />
-                <Select value={selectedCompany} onValueChange={(value) => setSelectedCompany(value)}>
-                  <SelectTrigger className="h-10 w-[200px]">
-                    <SelectValue placeholder={t("filter.company.placeholder")} />
-                  </SelectTrigger>
-                  <SelectContent>
-                    <SelectItem value="all">{t("filter.company.all")}</SelectItem>
-                    {companies.map((company) => (
-                      <SelectItem key={company.company_code} value={company.company_code}>
-                        {company.company_name}
-                      </SelectItem>
-                    ))}
-                  </SelectContent>
-                </Select>
-                {selectedCompany !== "all" && (
-                  <Button variant="ghost" size="sm" onClick={() => setSelectedCompany("all")} className="h-8 w-8 p-0">
-                    <X className="h-4 w-4" />
-                  </Button>
-                )}
-              </div>
-            )}
-          </div>
+          <h2 className="text-xl font-semibold">{t("roles.list.title")} ({roleGroups.length})</h2>
 
           <Button onClick={handleCreateRole} className="gap-2">
             <Plus className="h-4 w-4" />
@@ -346,15 +279,6 @@ export default function RolesPage() {
 
                   {/* 정보 */}
                   <div className="space-y-2 border-t pt-4">
-                    {/* 최고 관리자는 회사명 표시 */}
-                    {isSuperAdmin && (
-                      <div className="flex justify-between text-sm">
-                        <span className="text-muted-foreground">{t("label.company")}</span>
-                        <span className="font-medium">
-                          {companies.find((c) => c.company_code === role.companyCode)?.company_name || role.companyCode}
-                        </span>
-                      </div>
-                    )}
                     <div className="flex justify-between text-sm">
                       <span className="text-muted-foreground flex items-center gap-1">
                         <Users className="h-3 w-3" />
diff --git a/frontend/components/admin/RoleFormModal.tsx b/frontend/components/admin/RoleFormModal.tsx
index b6e0fd0b..f2ac5809 100644
--- a/frontend/components/admin/RoleFormModal.tsx
+++ b/frontend/components/admin/RoleFormModal.tsx
@@ -13,13 +13,9 @@ import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
 import { Label } from "@/components/ui/label";
 import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from "@/components/ui/select";
-import { Command, CommandEmpty, CommandGroup, CommandInput, CommandItem, CommandList } from "@/components/ui/command";
-import { Popover, PopoverContent, PopoverTrigger } from "@/components/ui/popover";
 import { roleAPI, RoleGroup } from "@/lib/api/role";
 import { useAuth } from "@/hooks/useAuth";
-import { AlertCircle, Check, ChevronsUpDown } from "lucide-react";
-import { cn } from "@/lib/utils";
-import { companyAPI } from "@/lib/api/company";
+import { AlertCircle } from "lucide-react";
 
 interface RoleFormModalProps {
   isOpen: boolean;
@@ -42,14 +38,10 @@ export function RoleFormModal({ isOpen, onClose, onSuccess, editingRole }: RoleF
   const { user: currentUser } = useAuth();
   const isEditMode = !!editingRole;
 
-  // 최고 관리자 여부
-  const isSuperAdmin = currentUser?.companyCode === "*" && currentUser?.userType === "SUPER_ADMIN";
-
   // 폼 데이터
   const [formData, setFormData] = useState({
     authName: "",
     authCode: "",
-    companyCode: currentUser?.companyCode || "",
     status: "active",
   });
 
@@ -59,14 +51,9 @@ export function RoleFormModal({ isOpen, onClose, onSuccess, editingRole }: RoleF
   const [alertMessage, setAlertMessage] = useState("");
   const [alertType, setAlertType] = useState<"success" | "error" | "info">("info");
 
-  // 회사 목록 (최고 관리자용)
-  const [companies, setCompanies] = useState<Array<{ company_code: string; company_name: string }>>([]);
-  const [isLoadingCompanies, setIsLoadingCompanies] = useState(false);
-  const [companyComboOpen, setCompanyComboOpen] = useState(false);
-
   // 폼 유효성 검사
   const isFormValid = useMemo(() => {
-    return formData.authName.trim() !== "" && formData.authCode.trim() !== "" && formData.companyCode.trim() !== "";
+    return formData.authName.trim() !== "" && formData.authCode.trim() !== "";
   }, [formData]);
 
   // 알림 표시
@@ -77,38 +64,14 @@ export function RoleFormModal({ isOpen, onClose, onSuccess, editingRole }: RoleF
     setTimeout(() => setShowAlert(false), 3000);
   }, []);
 
-  // 회사 목록 로드 (최고 관리자만)
-  const loadCompanies = useCallback(async () => {
-    if (!isSuperAdmin) return;
-
-    setIsLoadingCompanies(true);
-    try {
-      // companyAPI.getList()는 Promise<Company[]>를 반환하므로 직접 사용
-      const companies = await companyAPI.getList();
-      console.log("📋 회사 목록 로드 성공:", companies);
-      setCompanies(companies);
-    } catch (error) {
-      console.error("❌ 회사 목록 로드 오류:", error);
-      displayAlert("회사 목록을 불러오는데 실패했습니다.", "error");
-    } finally {
-      setIsLoadingCompanies(false);
-    }
-  }, [isSuperAdmin, displayAlert]);
-
   // 초기화
   useEffect(() => {
     if (isOpen) {
-      // 최고 관리자이고 생성 모드일 때만 회사 목록 로드
-      if (isSuperAdmin && !isEditMode) {
-        loadCompanies();
-      }
-
       if (isEditMode && editingRole) {
         // 수정 모드: 기존 데이터 로드
         setFormData({
           authName: editingRole.authName || "",
           authCode: editingRole.authCode || "",
-          companyCode: editingRole.companyCode || "",
           status: editingRole.status || "active",
         });
       } else {
@@ -116,13 +79,12 @@ export function RoleFormModal({ isOpen, onClose, onSuccess, editingRole }: RoleF
         setFormData({
           authName: "",
           authCode: "",
-          companyCode: currentUser?.companyCode || "",
           status: "active",
         });
       }
       setShowAlert(false);
     }
-  }, [isOpen, isEditMode, editingRole, currentUser?.companyCode, isSuperAdmin, loadCompanies]);
+  }, [isOpen, isEditMode, editingRole]);
 
   // 입력 핸들러
   const handleInputChange = useCallback((field: string, value: string) => {
@@ -148,11 +110,11 @@ export function RoleFormModal({ isOpen, onClose, onSuccess, editingRole }: RoleF
           status: formData.status,
         });
       } else {
-        // 생성
+        // 생성 (단일 테넌시: 현재 사용자 회사 코드 사용)
         response = await roleAPI.create({
           authName: formData.authName,
           authCode: formData.authCode,
-          companyCode: formData.companyCode,
+          companyCode: currentUser?.companyCode || "",
         });
       }
 
@@ -226,102 +188,6 @@ export function RoleFormModal({ isOpen, onClose, onSuccess, editingRole }: RoleF
             </p>
           </div>
 
-          {/* 회사 (수정 모드에서는 비활성화) */}
-          {isEditMode ? (
-            <div>
-              <Label htmlFor="companyCode" className="text-xs sm:text-sm">
-                회사
-              </Label>
-              <Input
-                id="companyCode"
-                value={formData.companyCode}
-                disabled
-                className="bg-muted h-8 cursor-not-allowed text-xs sm:h-10 sm:text-sm"
-              />
-              <p className="text-muted-foreground mt-1 text-[10px] sm:text-xs">회사 코드는 수정할 수 없습니다.</p>
-            </div>
-          ) : (
-            <div>
-              <Label htmlFor="companyCode" className="text-xs sm:text-sm">
-                회사 <span className="text-destructive">*</span>
-              </Label>
-              {isSuperAdmin ? (
-                <>
-                  <Popover open={companyComboOpen} onOpenChange={setCompanyComboOpen}>
-                    <PopoverTrigger asChild>
-                      <Button
-                        variant="outline"
-                        role="combobox"
-                        aria-expanded={companyComboOpen}
-                        className="h-8 w-full justify-between text-xs sm:h-10 sm:text-sm"
-                        disabled={isLoading || isLoadingCompanies}
-                      >
-                        {formData.companyCode
-                          ? companies.find((company) => company.company_code === formData.companyCode)?.company_name ||
-                            formData.companyCode
-                          : "회사 선택..."}
-                        <ChevronsUpDown className="ml-2 h-4 w-4 shrink-0 opacity-50" />
-                      </Button>
-                    </PopoverTrigger>
-                    <PopoverContent
-                      className="p-0"
-                      style={{ width: "var(--radix-popover-trigger-width)" }}
-                      align="start"
-                    >
-                      <Command>
-                        <CommandInput placeholder="회사 검색..." className="text-xs sm:text-sm" />
-                        <CommandList>
-                          <CommandEmpty className="text-xs sm:text-sm">
-                            {isLoadingCompanies ? "로딩 중..." : "회사를 찾을 수 없습니다."}
-                          </CommandEmpty>
-                          <CommandGroup>
-                            {companies.map((company) => (
-                              <CommandItem
-                                key={company.company_code}
-                                value={`${company.company_code} ${company.company_name}`}
-                                onSelect={() => {
-                                  handleInputChange("companyCode", company.company_code);
-                                  setCompanyComboOpen(false);
-                                }}
-                                className="text-xs sm:text-sm"
-                              >
-                                <Check
-                                  className={cn(
-                                    "mr-2 h-4 w-4",
-                                    formData.companyCode === company.company_code ? "opacity-100" : "opacity-0",
-                                  )}
-                                />
-                                <div className="flex flex-col">
-                                  <span className="font-medium">{company.company_name}</span>
-                                  <span className="text-muted-foreground text-[10px]">{company.company_code}</span>
-                                </div>
-                              </CommandItem>
-                            ))}
-                          </CommandGroup>
-                        </CommandList>
-                      </Command>
-                    </PopoverContent>
-                  </Popover>
-                  <p className="text-muted-foreground mt-1 text-[10px] sm:text-xs">
-                    모든 회사에 권한 그룹을 생성할 수 있습니다.
-                  </p>
-                </>
-              ) : (
-                <>
-                  <Input
-                    id="companyCode"
-                    value={formData.companyCode}
-                    disabled
-                    className="bg-muted h-8 cursor-not-allowed text-xs sm:h-10 sm:text-sm"
-                  />
-                  <p className="text-muted-foreground mt-1 text-[10px] sm:text-xs">
-                    자신의 회사에만 권한 그룹을 생성할 수 있습니다.
-                  </p>
-                </>
-              )}
-            </div>
-          )}
-
           {/* 상태 (수정 모드에서만 표시) */}
           {isEditMode && (
             <div>
diff --git a/frontend/components/messenger/MessageInput.tsx b/frontend/components/messenger/MessageInput.tsx
index 241fcae7..dcf9fffc 100644
--- a/frontend/components/messenger/MessageInput.tsx
+++ b/frontend/components/messenger/MessageInput.tsx
@@ -39,7 +39,7 @@ function MessageInput({ roomId, onTypingStart, onTypingStop }: MessageInputProps
   const { data: users } = useCompanyUsers();
 
   const filteredMentionUsers = mentionQuery !== null && users
-    ? users.filter((u) => u.userName.toLowerCase().includes(mentionQuery.toLowerCase())).slice(0, 5)
+    ? users.filter((u) => u.userName?.toLowerCase().includes(mentionQuery.toLowerCase())).slice(0, 5)
     : [];
 
   // Revoke object URLs when pending files change or component unmounts
diff --git a/frontend/components/messenger/NewRoomModal.tsx b/frontend/components/messenger/NewRoomModal.tsx
index 09fa513c..fde5b435 100644
--- a/frontend/components/messenger/NewRoomModal.tsx
+++ b/frontend/components/messenger/NewRoomModal.tsx
@@ -35,10 +35,11 @@ export function NewRoomModal({ open, onOpenChange, userStatuses }: NewRoomModalP
   const createRoom = useCreateRoom();
   const { selectRoom } = useMessengerContext();
 
+  const q = search.toLowerCase();
   const filtered = users.filter(
     (u) =>
-      u.userName.toLowerCase().includes(search.toLowerCase()) ||
-      (u.deptName && u.deptName.toLowerCase().includes(search.toLowerCase()))
+      u.userName?.toLowerCase().includes(q) ||
+      u.deptName?.toLowerCase().includes(q)
   );
 
   const toggleUser = (userId: string) => {