diff --git a/server/skillhub-app/src/test/java/com/iflytek/skillhub/domain/social/SkillSubscriptionServiceTest.java b/server/skillhub-app/src/test/java/com/iflytek/skillhub/domain/social/SkillSubscriptionServiceTest.java
new file mode 100644
index 00000000..5e47524d
--- /dev/null
+++ b/server/skillhub-app/src/test/java/com/iflytek/skillhub/domain/social/SkillSubscriptionServiceTest.java
@@ -0,0 +1,105 @@
+package com.iflytek.skillhub.domain.social;
+
+import com.iflytek.skillhub.domain.skill.Skill;
+import com.iflytek.skillhub.domain.skill.SkillRepository;
+import com.iflytek.skillhub.domain.social.event.SkillSubscribedEvent;
+import com.iflytek.skillhub.domain.social.event.SkillUnsubscribedEvent;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.ArgumentCaptor;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.springframework.context.ApplicationEventPublisher;
+
+import java.util.Optional;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.*;
+
+@ExtendWith(MockitoExtension.class)
+class SkillSubscriptionServiceTest {
+
+    @Mock private SkillSubscriptionRepository subscriptionRepository;
+    @Mock private SkillRepository skillRepository;
+    @Mock private ApplicationEventPublisher eventPublisher;
+
+    private SkillSubscriptionService service;
+
+    @BeforeEach
+    void setUp() {
+        service = new SkillSubscriptionService(subscriptionRepository, skillRepository, eventPublisher);
+    }
+
+    @Test
+    void subscribe_createsSubscriptionAndPublishesEvent() {
+        when(skillRepository.findById(1L)).thenReturn(Optional.of(mock(Skill.class)));
+        when(subscriptionRepository.findBySkillIdAndUserId(1L, "user-1")).thenReturn(Optional.empty());
+        when(subscriptionRepository.save(any())).thenAnswer(inv -> inv.getArgument(0));
+
+        service.subscribe(1L, "user-1");
+
+        verify(subscriptionRepository).save(any(SkillSubscription.class));
+        verify(skillRepository).incrementSubscriptionCount(1L);
+        ArgumentCaptor<SkillSubscribedEvent> captor = ArgumentCaptor.forClass(SkillSubscribedEvent.class);
+        verify(eventPublisher).publishEvent(captor.capture());
+        assertThat(captor.getValue().skillId()).isEqualTo(1L);
+        assertThat(captor.getValue().userId()).isEqualTo("user-1");
+    }
+
+    @Test
+    void subscribe_idempotent_doesNotDuplicate() {
+        when(skillRepository.findById(1L)).thenReturn(Optional.of(mock(Skill.class)));
+        when(subscriptionRepository.findBySkillIdAndUserId(1L, "user-1"))
+                .thenReturn(Optional.of(mock(SkillSubscription.class)));
+
+        service.subscribe(1L, "user-1");
+
+        verify(subscriptionRepository, never()).save(any());
+        verify(eventPublisher, never()).publishEvent(any());
+    }
+
+    @Test
+    void unsubscribe_deletesSubscriptionAndPublishesEvent() {
+        when(skillRepository.findById(1L)).thenReturn(Optional.of(mock(Skill.class)));
+        SkillSubscription existing = mock(SkillSubscription.class);
+        when(subscriptionRepository.findBySkillIdAndUserId(1L, "user-1")).thenReturn(Optional.of(existing));
+
+        service.unsubscribe(1L, "user-1");
+
+        verify(subscriptionRepository).delete(existing);
+        verify(skillRepository).decrementSubscriptionCount(1L);
+        ArgumentCaptor<SkillUnsubscribedEvent> captor = ArgumentCaptor.forClass(SkillUnsubscribedEvent.class);
+        verify(eventPublisher).publishEvent(captor.capture());
+        assertThat(captor.getValue().skillId()).isEqualTo(1L);
+    }
+
+    @Test
+    void unsubscribe_noOp_whenNotSubscribed() {
+        when(skillRepository.findById(1L)).thenReturn(Optional.of(mock(Skill.class)));
+        when(subscriptionRepository.findBySkillIdAndUserId(1L, "user-1")).thenReturn(Optional.empty());
+
+        service.unsubscribe(1L, "user-1");
+
+        verify(subscriptionRepository, never()).delete(any());
+        verify(eventPublisher, never()).publishEvent(any());
+    }
+
+    @Test
+    void isSubscribed_returnsTrue_whenSubscriptionExists() {
+        when(skillRepository.findById(1L)).thenReturn(Optional.of(mock(Skill.class)));
+        when(subscriptionRepository.findBySkillIdAndUserId(1L, "user-1"))
+                .thenReturn(Optional.of(mock(SkillSubscription.class)));
+
+        assertThat(service.isSubscribed(1L, "user-1")).isTrue();
+    }
+
+    @Test
+    void isSubscribed_returnsFalse_whenNoSubscription() {
+        when(skillRepository.findById(1L)).thenReturn(Optional.of(mock(Skill.class)));
+        when(subscriptionRepository.findBySkillIdAndUserId(1L, "user-1")).thenReturn(Optional.empty());
+
+        assertThat(service.isSubscribed(1L, "user-1")).isFalse();
+    }
+}
diff --git a/server/skillhub-app/src/test/java/com/iflytek/skillhub/service/MySkillAppServiceTest.java b/server/skillhub-app/src/test/java/com/iflytek/skillhub/service/MySkillAppServiceTest.java
index a4497731..c4faf136 100644
--- a/server/skillhub-app/src/test/java/com/iflytek/skillhub/service/MySkillAppServiceTest.java
+++ b/server/skillhub-app/src/test/java/com/iflytek/skillhub/service/MySkillAppServiceTest.java
@@ -15,6 +15,7 @@ import com.iflytek.skillhub.domain.skill.SkillVisibility;
 import com.iflytek.skillhub.domain.skill.service.SkillLifecycleProjectionService;
 import com.iflytek.skillhub.domain.social.SkillStar;
 import com.iflytek.skillhub.domain.social.SkillStarRepository;
+import com.iflytek.skillhub.domain.social.SkillSubscriptionRepository;
 import com.iflytek.skillhub.repository.JpaMySkillQueryRepository;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
@@ -50,6 +51,9 @@ class MySkillAppServiceTest {
     @Mock
     private SkillStarRepository skillStarRepository;
 
+    @Mock
+    private SkillSubscriptionRepository skillSubscriptionRepository;
+
     @Mock
     private PromotionRequestRepository promotionRequestRepository;
 
@@ -69,6 +73,7 @@ class MySkillAppServiceTest {
                 skillRepository,
                 skillVersionRepository,
                 skillStarRepository,
+                skillSubscriptionRepository,
                 mySkillQueryRepository,
                 skillLifecycleProjectionService
         );