diff --git a/ai/migrations/0004_add_is_pinned_to_aianalysis.py b/ai/migrations/0004_add_is_pinned_to_aianalysis.py
new file mode 100644
index 0000000..d37cdad
--- /dev/null
+++ b/ai/migrations/0004_add_is_pinned_to_aianalysis.py
@@ -0,0 +1,18 @@
+# Generated by Django 6.0.4 on 2026-06-04 14:39
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('ai', '0003_alter_aianalysis_model'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='aianalysis',
+            name='is_pinned',
+            field=models.BooleanField(default=False),
+        ),
+    ]
diff --git a/ai/models.py b/ai/models.py
index c78802c..12bf55a 100644
--- a/ai/models.py
+++ b/ai/models.py
@@ -11,6 +11,7 @@ class AIAnalysis(models.Model):
     system_prompt = models.TextField()
     user_prompt = models.TextField()
     analysis = models.TextField()
+    is_pinned = models.BooleanField(default=False)
     create_time = models.DateTimeField(auto_now_add=True)
 
     class Meta:
diff --git a/ai/serializers.py b/ai/serializers.py
index d73955f..cc0a918 100644
--- a/ai/serializers.py
+++ b/ai/serializers.py
@@ -9,7 +9,7 @@ class AIAnalysisListSerializer(serializers.ModelSerializer):
 
     class Meta:
         model = AIAnalysis
-        fields = ["id", "create_time", "username", "class_name"]
+        fields = ["id", "create_time", "username", "class_name", "is_pinned"]
 
 
 class AIAnalysisDetailSerializer(serializers.ModelSerializer):
diff --git a/ai/urls/oj.py b/ai/urls/oj.py
index ee332d1..37c81de 100644
--- a/ai/urls/oj.py
+++ b/ai/urls/oj.py
@@ -7,6 +7,7 @@ from ..views.oj import (
     AIHeatmapDataAPI,
     AIHintAPI,
     AILoginSummaryAPI,
+    AIPinnedReportAPI,
     ClassPKAnalysisAPI,
 )
 
@@ -17,5 +18,6 @@ urlpatterns = [
     path("ai/hint", AIHintAPI.as_view()),
     path("ai/heatmap", AIHeatmapDataAPI.as_view()),
     path("ai/login_summary", AILoginSummaryAPI.as_view()),
+    path("ai/pinned", AIPinnedReportAPI.as_view()),
     path("ai/class_pk", ClassPKAnalysisAPI.as_view()),
 ]
diff --git a/ai/views/admin.py b/ai/views/admin.py
index d158d0a..fd42704 100644
--- a/ai/views/admin.py
+++ b/ai/views/admin.py
@@ -1,5 +1,4 @@
 from account.decorators import teacher_admin_required
-from account.models import User
 from utils.api import APIView
 
 from ..models import AIAnalysis
@@ -21,10 +20,26 @@ class AIAnalysisAdminAPI(APIView):
 
         username = request.GET.get("username")
         if username:
-            try:
-                user = User.objects.get(username=username)
-            except User.DoesNotExist:
-                return self.error("User not found")
-            qs = qs.filter(user=user)
+            qs = qs.filter(user__username__icontains=username)
+
+        if request.GET.get("pinned_only") == "true":
+            pinned = qs.filter(is_pinned=True)
+            return self.success(AIAnalysisListSerializer(pinned, many=True).data)
 
         return self.success(self.paginate_data(request, qs, AIAnalysisListSerializer))
+
+    @teacher_admin_required
+    def post(self, request):
+        report_id = request.data.get("id")
+        try:
+            report = AIAnalysis.objects.select_related("user").get(id=report_id)
+        except AIAnalysis.DoesNotExist:
+            return self.error("AIAnalysis not found")
+
+        if report.is_pinned:
+            report.is_pinned = False
+        else:
+            AIAnalysis.objects.filter(user=report.user, is_pinned=True).update(is_pinned=False)
+            report.is_pinned = True
+        report.save(update_fields=["is_pinned"])
+        return self.success({"is_pinned": report.is_pinned})
diff --git a/ai/views/oj.py b/ai/views/oj.py
index 11350b1..a6a52ff 100644
--- a/ai/views/oj.py
+++ b/ai/views/oj.py
@@ -14,6 +14,7 @@ from django.utils.dateparse import parse_datetime
 from account.decorators import login_required, teacher_admin_required
 from account.models import User
 from ai.models import AIAnalysis
+from ai.serializers import AIAnalysisDetailSerializer
 from flowchart.models import FlowchartSubmission, FlowchartSubmissionStatus
 from problem.models import Problem
 from submission.models import JudgeStatus, Submission
@@ -800,6 +801,16 @@ class ClassPKAnalysisAPI(APIView):
         return "\n".join(lines)
 
 
+class AIPinnedReportAPI(APIView):
+    @login_required
+    def get(self, request):
+        try:
+            report = AIAnalysis.objects.get(user=request.user, is_pinned=True)
+        except AIAnalysis.DoesNotExist:
+            return self.success(None)
+        return self.success(AIAnalysisDetailSerializer(report).data)
+
+
 class AIHintAPI(APIView):
     @login_required
     def post(self, request):