diff --git a/mirai-core-mock/src/internal/contact/MockGroupImpl.kt b/mirai-core-mock/src/internal/contact/MockGroupImpl.kt
index 257670ee0..75a18d32a 100644
--- a/mirai-core-mock/src/internal/contact/MockGroupImpl.kt
+++ b/mirai-core-mock/src/internal/contact/MockGroupImpl.kt
@@ -108,10 +108,11 @@ internal class MockGroupImpl(
     }
 
     override suspend fun changeOwner(member: NormalMember) {
+        if (member === owner) return
         val oldOwner = owner
         val oldPerm = member.permission
-        member.mock().mockApi.permission = MemberPermission.OWNER
         oldOwner.mock().mockApi.permission = MemberPermission.MEMBER
+        member.mock().mockApi.permission = MemberPermission.OWNER
         owner = member
 
         if (member === botAsMember) {
diff --git a/mirai-core-mock/src/internal/contact/MockNormalMemberImpl.kt b/mirai-core-mock/src/internal/contact/MockNormalMemberImpl.kt
index 7d505df5a..0ec295bae 100644
--- a/mirai-core-mock/src/internal/contact/MockNormalMemberImpl.kt
+++ b/mirai-core-mock/src/internal/contact/MockNormalMemberImpl.kt
@@ -162,7 +162,7 @@ internal class MockNormalMemberImpl(
         val newPerm = if (operation) MemberPermission.ADMINISTRATOR else MemberPermission.MEMBER
         if (newPerm != permission) {
             val oldPerm = permission
-            mockApi.permission = oldPerm
+            mockApi.permission = newPerm
             MemberPermissionChangeEvent(this, oldPerm, newPerm).broadcast()
         }
     }
diff --git a/mirai-core-mock/test/mock/MockMemberTest.kt b/mirai-core-mock/test/mock/MockMemberTest.kt
index 653d534a6..4fdd7d422 100644
--- a/mirai-core-mock/test/mock/MockMemberTest.kt
+++ b/mirai-core-mock/test/mock/MockMemberTest.kt
@@ -10,10 +10,14 @@
 package net.mamoe.mirai.mock.test.mock
 
 import net.mamoe.mirai.contact.MemberPermission
+import net.mamoe.mirai.event.events.BotGroupPermissionChangeEvent
+import net.mamoe.mirai.event.events.MemberPermissionChangeEvent
 import net.mamoe.mirai.mock.test.MockBotTestBase
 import net.mamoe.mirai.mock.utils.simpleMemberInfo
 import org.junit.jupiter.api.Test
+import kotlin.test.assertEquals
 import kotlin.test.assertNotEquals
+import kotlin.test.assertSame
 
 internal class MockMemberTest : MockBotTestBase() {
     @Test
@@ -21,4 +25,53 @@ internal class MockMemberTest : MockBotTestBase() {
         val m = bot.addGroup(111, "aaa").addMember(simpleMemberInfo(222, "bbb", permission = MemberPermission.MEMBER))
         assertNotEquals("", m.avatarUrl)
     }
+
+    @Test
+    internal fun changeOwner() = runTest {
+        val group = bot.addGroup(111, "aaa")
+        val member = group.addMember(simpleMemberInfo(222, "bbb", permission = MemberPermission.MEMBER))
+        val events = runAndReceiveEventBroadcast {
+            group.changeOwner(member)
+            assertSame(member, group.owner)
+            assertSame(MemberPermission.OWNER, member.permission)
+        }
+        assertEquals(2, events.size)
+        assertIsInstance<MemberPermissionChangeEvent>(events[0]) {
+            assertSame(member, this.member)
+            assertSame(MemberPermission.OWNER, new)
+            assertSame(MemberPermission.MEMBER, origin)
+            assertSame(group, this.group)
+        }
+        assertIsInstance<BotGroupPermissionChangeEvent>(events[1]) {
+            assertSame(MemberPermission.MEMBER, new)
+            assertSame(MemberPermission.OWNER, origin)
+            assertSame(group, this.group)
+        }
+    }
+
+    @Test
+    internal fun modifyAdmin() = runTest {
+        val group = bot.addGroup(111, "aaa")
+        group.changeOwner(group.botAsMember)
+        val m = group.addMember(simpleMemberInfo(222, "bbb", permission = MemberPermission.MEMBER))
+        val events = runAndReceiveEventBroadcast {
+            m.modifyAdmin(true)
+            assertEquals(MemberPermission.ADMINISTRATOR, m.permission)
+            m.modifyAdmin(false)
+            assertEquals(MemberPermission.MEMBER, m.permission)
+        }
+        assertEquals(2, events.size)
+        assertIsInstance<MemberPermissionChangeEvent>(events[0]) {
+            assertSame(m, member)
+            assertSame(MemberPermission.MEMBER, origin)
+            assertSame(MemberPermission.ADMINISTRATOR, new)
+            assertSame(group, this.group)
+        }
+        assertIsInstance<MemberPermissionChangeEvent>(events[1]) {
+            assertSame(m, member)
+            assertSame(MemberPermission.ADMINISTRATOR, origin)
+            assertSame(MemberPermission.MEMBER, new)
+            assertSame(group, this.group)
+        }
+    }
 }
\ No newline at end of file