diff --git a/messages/en.json b/messages/en.json
index f7cf6a1e..ce6120a4 100644
--- a/messages/en.json
+++ b/messages/en.json
@@ -502,8 +502,14 @@
         "admin": "Admins",
         "user": "Users",
         "verified": "Verified",
-        "unverified": "Unverified"
-      }
+        "unverified": "Unverified",
+        "flagged": "Flagged"
+      },
+      "flag": "Flag User",
+      "unflag": "Unflag User",
+      "flagged": "User flagged",
+      "unflagged": "User unflagged",
+      "flagFailed": "Failed to update flag status"
     },
     "categories": {
       "title": "Category Management",
diff --git a/prisma/migrations/20251222132600_add_user_flagged_and_unusual_activity/migration.sql b/prisma/migrations/20251222132600_add_user_flagged_and_unusual_activity/migration.sql
new file mode 100644
index 00000000..20f2dfee
--- /dev/null
+++ b/prisma/migrations/20251222132600_add_user_flagged_and_unusual_activity/migration.sql
@@ -0,0 +1,7 @@
+-- AlterEnum
+ALTER TYPE "DelistReason" ADD VALUE 'UNUSUAL_ACTIVITY';
+
+-- AlterTable
+ALTER TABLE "users" ADD COLUMN "flagged" BOOLEAN NOT NULL DEFAULT false;
+ALTER TABLE "users" ADD COLUMN "flaggedAt" TIMESTAMP(3);
+ALTER TABLE "users" ADD COLUMN "flaggedReason" TEXT;
diff --git a/prisma/schema.prisma b/prisma/schema.prisma
index beb828c2..8a5bbeb8 100644
--- a/prisma/schema.prisma
+++ b/prisma/schema.prisma
@@ -23,6 +23,9 @@ model User {
   githubUsername            String?
   apiKey                    String?                @unique
   mcpPromptsPublicByDefault Boolean                @default(false)
+  flagged                   Boolean                @default(false)
+  flaggedAt                 DateTime?
+  flaggedReason             String?
   accounts                  Account[]
   subscriptions  CategorySubscription[]
   changeRequests ChangeRequest[]
@@ -408,4 +411,5 @@ enum DelistReason {
   LOW_QUALITY
   NOT_LLM_INSTRUCTION
   MANUAL
+  UNUSUAL_ACTIVITY
 }
diff --git a/src/app/api/admin/users/[id]/route.ts b/src/app/api/admin/users/[id]/route.ts
index 15b39dd4..c0708d34 100644
--- a/src/app/api/admin/users/[id]/route.ts
+++ b/src/app/api/admin/users/[id]/route.ts
@@ -15,10 +15,16 @@ export async function PATCH(
 
     const { id } = await params;
     const body = await request.json();
-    const { role, verified } = body;
+    const { role, verified, flagged, flaggedReason } = body;
 
     // Build update data
-    const updateData: { role?: "ADMIN" | "USER"; verified?: boolean } = {};
+    const updateData: { 
+      role?: "ADMIN" | "USER"; 
+      verified?: boolean;
+      flagged?: boolean;
+      flaggedAt?: Date | null;
+      flaggedReason?: string | null;
+    } = {};
 
     if (role !== undefined) {
       if (!["ADMIN", "USER"].includes(role)) {
@@ -31,9 +37,33 @@ export async function PATCH(
       updateData.verified = verified;
     }
 
+    if (flagged !== undefined) {
+      updateData.flagged = flagged;
+      if (flagged) {
+        updateData.flaggedAt = new Date();
+        updateData.flaggedReason = flaggedReason || null;
+      } else {
+        updateData.flaggedAt = null;
+        updateData.flaggedReason = null;
+      }
+    }
+
     const user = await db.user.update({
       where: { id },
       data: updateData,
+      select: {
+        id: true,
+        email: true,
+        username: true,
+        name: true,
+        avatar: true,
+        role: true,
+        verified: true,
+        flagged: true,
+        flaggedAt: true,
+        flaggedReason: true,
+        createdAt: true,
+      },
     });
 
     return NextResponse.json(user);
diff --git a/src/app/api/admin/users/route.ts b/src/app/api/admin/users/route.ts
index 79c63563..1018153f 100644
--- a/src/app/api/admin/users/route.ts
+++ b/src/app/api/admin/users/route.ts
@@ -41,6 +41,7 @@ export async function GET(request: NextRequest) {
       OR?: Array<{ email?: { contains: string; mode: "insensitive" }; username?: { contains: string; mode: "insensitive" }; name?: { contains: string; mode: "insensitive" } }>;
       role?: "ADMIN" | "USER";
       verified?: boolean;
+      flagged?: boolean;
     };
 
     const filterConditions: WhereCondition = {};
@@ -58,6 +59,9 @@ export async function GET(request: NextRequest) {
       case "unverified":
         filterConditions.verified = false;
         break;
+      case "flagged":
+        filterConditions.flagged = true;
+        break;
       default:
         // "all" - no filter
         break;
@@ -95,6 +99,9 @@ export async function GET(request: NextRequest) {
           avatar: true,
           role: true,
           verified: true,
+          flagged: true,
+          flaggedAt: true,
+          flaggedReason: true,
           createdAt: true,
           _count: {
             select: {
diff --git a/src/app/api/prompts/route.ts b/src/app/api/prompts/route.ts
index 03287d69..1ba988b0 100644
--- a/src/app/api/prompts/route.ts
+++ b/src/app/api/prompts/route.ts
@@ -48,6 +48,13 @@ export async function POST(request: Request) {
 
     const { title, description, content, type, structuredFormat, categoryId, tagIds, contributorIds, isPrivate, mediaUrl, requiresMediaUpload, requiredMediaType, requiredMediaCount } = parsed.data;
 
+    // Check if user is flagged (for auto-delisting)
+    const currentUser = await db.user.findUnique({
+      where: { id: session.user.id },
+      select: { flagged: true },
+    });
+    const isUserFlagged = currentUser?.flagged ?? false;
+
     // Rate limit: Check if user created a prompt in the last 30 seconds
     const thirtySecondsAgo = new Date(Date.now() - 30 * 1000);
     const recentPrompt = await db.prompt.findFirst({
@@ -135,6 +142,7 @@ export async function POST(request: Request) {
     const slug = await generatePromptSlug(title);
 
     // Create prompt with tags
+    // Auto-delist if user is flagged
     const prompt = await db.prompt.create({
       data: {
         title,
@@ -150,6 +158,12 @@ export async function POST(request: Request) {
         requiredMediaCount: requiresMediaUpload ? requiredMediaCount : null,
         authorId: session.user.id,
         categoryId: categoryId || null,
+        // Auto-delist prompts from flagged users
+        ...(isUserFlagged && {
+          isUnlisted: true,
+          unlistedAt: new Date(),
+          delistReason: "UNUSUAL_ACTIVITY",
+        }),
         tags: {
           create: tagIds.map((tagId) => ({
             tagId,
diff --git a/src/components/admin/users-table.tsx b/src/components/admin/users-table.tsx
index 4e9b2031..f1e5b372 100644
--- a/src/components/admin/users-table.tsx
+++ b/src/components/admin/users-table.tsx
@@ -4,7 +4,7 @@ import { useState, useEffect, useCallback } from "react";
 import { useRouter } from "next/navigation";
 import { useTranslations, useLocale } from "next-intl";
 import { formatDistanceToNow } from "@/lib/date";
-import { MoreHorizontal, Shield, User, Trash2, BadgeCheck, Search, Loader2, ChevronLeft, ChevronRight, Filter } from "lucide-react";
+import { MoreHorizontal, Shield, User, Trash2, BadgeCheck, Search, Loader2, ChevronLeft, ChevronRight, Filter, Flag, AlertTriangle } from "lucide-react";
 import { Avatar, AvatarFallback, AvatarImage } from "@/components/ui/avatar";
 import { Badge } from "@/components/ui/badge";
 import { Button } from "@/components/ui/button";
@@ -51,6 +51,9 @@ interface UserData {
   avatar: string | null;
   role: "ADMIN" | "USER";
   verified: boolean;
+  flagged: boolean;
+  flaggedAt: string | null;
+  flaggedReason: string | null;
   createdAt: string;
   _count: {
     prompts: number;
@@ -148,12 +151,31 @@ export function UsersTable() {
       if (!res.ok) throw new Error("Failed to update verification");
 
       toast.success(verified ? t("verified") : t("unverified"));
+      fetchUsers(currentPage, searchQuery, userFilter);
       router.refresh();
     } catch {
       toast.error(t("verifyFailed"));
     }
   };
 
+  const handleFlagToggle = async (userId: string, flagged: boolean) => {
+    try {
+      const res = await fetch(`/api/admin/users/${userId}`, {
+        method: "PATCH",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify({ flagged, flaggedReason: flagged ? "Unusual activity" : null }),
+      });
+
+      if (!res.ok) throw new Error("Failed to update flag status");
+
+      toast.success(flagged ? t("flagged") : t("unflagged"));
+      fetchUsers(currentPage, searchQuery, userFilter);
+      router.refresh();
+    } catch {
+      toast.error(t("flagFailed"));
+    }
+  };
+
   const handleDelete = async () => {
     if (!deleteUserId) return;
 
@@ -195,6 +217,7 @@ export function UsersTable() {
               <SelectItem value="user">{t("filters.user")}</SelectItem>
               <SelectItem value="verified">{t("filters.verified")}</SelectItem>
               <SelectItem value="unverified">{t("filters.unverified")}</SelectItem>
+              <SelectItem value="flagged">{t("filters.flagged")}</SelectItem>
             </SelectContent>
           </Select>
           <div className="flex gap-2">
@@ -241,6 +264,7 @@ export function UsersTable() {
                       <div className="font-medium flex items-center gap-1 truncate">
                         {user.name || user.username}
                         {user.verified && <BadgeCheck className="h-4 w-4 text-blue-500 flex-shrink-0" />}
+                        {user.flagged && <AlertTriangle className="h-4 w-4 text-amber-500 flex-shrink-0" />}
                       </div>
                       <div className="text-xs text-muted-foreground">@{user.username}</div>
                     </div>
@@ -267,6 +291,10 @@ export function UsersTable() {
                         <BadgeCheck className="h-4 w-4 mr-2" />
                         {user.verified ? t("unverify") : t("verify")}
                       </DropdownMenuItem>
+                      <DropdownMenuItem onClick={() => handleFlagToggle(user.id, !user.flagged)}>
+                        <Flag className="h-4 w-4 mr-2" />
+                        {user.flagged ? t("unflag") : t("flag")}
+                      </DropdownMenuItem>
                       <DropdownMenuSeparator />
                       <DropdownMenuItem
                         className="text-destructive"
@@ -321,6 +349,7 @@ export function UsersTable() {
                       <div className="font-medium flex items-center gap-1">
                         {user.name || user.username}
                         {user.verified && <BadgeCheck className="h-4 w-4 text-blue-500" />}
+                        {user.flagged && <AlertTriangle className="h-4 w-4 text-amber-500" />}
                       </div>
                       <div className="text-xs text-muted-foreground">@{user.username}</div>
                     </div>
@@ -360,6 +389,10 @@ export function UsersTable() {
                         <BadgeCheck className="h-4 w-4 mr-2" />
                         {user.verified ? t("unverify") : t("verify")}
                       </DropdownMenuItem>
+                      <DropdownMenuItem onClick={() => handleFlagToggle(user.id, !user.flagged)}>
+                        <Flag className="h-4 w-4 mr-2" />
+                        {user.flagged ? t("unflag") : t("flag")}
+                      </DropdownMenuItem>
                       <DropdownMenuSeparator />
                       <DropdownMenuItem
                         className="text-destructive"