diff --git a/README.md b/README.md
index 81a399b..76e40bb 100644
--- a/README.md
+++ b/README.md
@@ -68,6 +68,21 @@ chatFallbackModelAliases: []
 
 修改配置后执行 `/jgpt reload`。其他模型、工具和实验功能按需配置，缺少依赖或凭据的可选工具不会启用。
 
+### 群聊触发限制
+
+默认开启 `requireOwnerInGroup`：只有配置的主人也在群内，JChatGPT 才允许触发群聊对话。请在 `Config.yml` 中填写主人的 QQ：
+
+```yaml
+ownerId: 123456789 # 替换为你的 QQ 号
+requireOwnerInGroup: true
+```
+
+此限制优先于聊天权限，覆盖 `@Bot`、引用回复、关键词以及连续会话触发。主人未配置、QQ 号无效、不在群内或成员查询失败时，均静默忽略，不发送拒绝提示。检查使用 Overflow 提供的当前群成员信息，不使用历史联系人快照；成员变动的生效时间取决于 Overflow 的同步。
+
+私聊仍按原有逻辑处理，聊天记录继续保存，画像相关配置、管理命令和其他插件不受此开关影响。开关限制新的消息触发，不会强制取消已经开始的模型请求或工具调用。设为 `false` 可恢复原有群聊触发行为，修改后执行 `/jgpt reload`。
+
+升级后此开关也默认开启；未配置 `ownerId` 时，所有群聊对话触发都会被忽略。
+
 ## 使用
 
 - 群聊中 `@Bot`，或回复 Bot 的消息
diff --git a/src/main/kotlin/JChatGPT.kt b/src/main/kotlin/JChatGPT.kt
index 89c3e67..57e357d 100644
--- a/src/main/kotlin/JChatGPT.kt
+++ b/src/main/kotlin/JChatGPT.kt
@@ -32,6 +32,7 @@ import top.jie65535.mirai.config.ModelConfig
 import top.jie65535.mirai.config.ModelConfigMigration
 import top.jie65535.mirai.conversation.ConversationContext
 import top.jie65535.mirai.conversation.ConversationEngine
+import top.jie65535.mirai.conversation.allowsGroupChatTrigger
 import top.jie65535.mirai.data.ChatHistoryStore
 import top.jie65535.mirai.data.ChatMessageRecord
 import top.jie65535.mirai.data.ContactSnapshotRefresher
@@ -175,6 +176,18 @@ object JChatGPT : KotlinPlugin(
     private suspend fun onMessage(event: MessageEvent) {
         if (LargeLanguageModels.chat == null) return
 
+        if (event is GroupMessageEvent && !allowsGroupChatTrigger(
+                requireOwnerInGroup = PluginConfig.requireOwnerInGroup,
+                ownerId = PluginConfig.ownerId,
+                isMember = { ownerId -> event.group[ownerId] != null },
+                onFailure = { cause ->
+                    logger.warning(
+                        "检查主人是否在群内失败，忽略群聊触发：bot=${event.bot.id}, group=${event.group.id}",
+                        cause,
+                    )
+                },
+            )) return
+
         if (ConversationEngine.isExpectedUser(event)) {
             if (shouldIgnoreBecauseMuted(event)) return
             if (ConversationEngine.resumeObserved(event)) return
diff --git a/src/main/kotlin/config/PluginConfig.kt b/src/main/kotlin/config/PluginConfig.kt
index caf6fbd..99119d3 100644
--- a/src/main/kotlin/config/PluginConfig.kt
+++ b/src/main/kotlin/config/PluginConfig.kt
@@ -21,6 +21,9 @@ object PluginConfig : AutoSavePluginConfig("Config") {
     @ValueDescription("主人QQ，AI可以通过工具向主人发起请求，会等待一段时间")
     val ownerId: Long by value()
 
+    @ValueDescription("是否仅在主人（ownerId）也在的群内允许聊天触发，默认开启；主人未配置、不在群内或无法确认时静默忽略。仅限制群聊，不影响私聊和聊天记录保存")
+    val requireOwnerInGroup: Boolean by value(true)
+
     @ValueDescription("OpenAI API base url")
     val openAiApi: String by value("https://dashscope.aliyuncs.com/compatible-mode/v1/")
 
diff --git a/src/main/kotlin/conversation/GroupChatTriggerPolicy.kt b/src/main/kotlin/conversation/GroupChatTriggerPolicy.kt
new file mode 100644
index 0000000..c501840
--- /dev/null
+++ b/src/main/kotlin/conversation/GroupChatTriggerPolicy.kt
@@ -0,0 +1,21 @@
+package top.jie65535.mirai.conversation
+
+import kotlinx.coroutines.CancellationException
+
+internal fun allowsGroupChatTrigger(
+    requireOwnerInGroup: Boolean,
+    ownerId: Long,
+    isMember: (Long) -> Boolean,
+    onFailure: (Exception) -> Unit,
+): Boolean {
+    if (!requireOwnerInGroup) return true
+    if (ownerId <= 0) return false
+    return try {
+        isMember(ownerId)
+    } catch (cause: CancellationException) {
+        throw cause
+    } catch (cause: Exception) {
+        onFailure(cause)
+        false
+    }
+}
diff --git a/src/test/kotlin/conversation/GroupChatTriggerPolicyTest.kt b/src/test/kotlin/conversation/GroupChatTriggerPolicyTest.kt
new file mode 100644
index 0000000..a2b8987
--- /dev/null
+++ b/src/test/kotlin/conversation/GroupChatTriggerPolicyTest.kt
@@ -0,0 +1,53 @@
+package top.jie65535.mirai.conversation
+
+import kotlinx.coroutines.CancellationException
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFalse
+import kotlin.test.assertFailsWith
+import kotlin.test.assertSame
+import kotlin.test.assertTrue
+
+class GroupChatTriggerPolicyTest {
+    @Test
+    fun disabledRestrictionDoesNotLookUpOwner() {
+        assertTrue(allowsGroupChatTrigger(false, 0, { error("Unexpected lookup") }, { throw it }))
+    }
+
+    @Test
+    fun missingOrInvalidOwnerBlocksWithoutLookup() {
+        for (ownerId in listOf(0L, -1L)) {
+            assertFalse(allowsGroupChatTrigger(true, ownerId, { error("Unexpected lookup") }, { throw it }))
+        }
+    }
+
+    @Test
+    fun configuredOwnerMustBePresentAndMembershipIsCheckedAgainOnEachTrigger() {
+        val members = mutableSetOf(123L, 456L)
+        val isMember: (Long) -> Boolean = { ownerId ->
+            assertEquals(123L, ownerId)
+            ownerId in members
+        }
+        assertTrue(allowsGroupChatTrigger(true, 123L, isMember, { throw it }))
+        members.remove(123L)
+        assertFalse(allowsGroupChatTrigger(true, 123L, isMember, { throw it }))
+        members.add(123L)
+        assertTrue(allowsGroupChatTrigger(true, 123L, isMember, { throw it }))
+    }
+
+    @Test
+    fun unavailableMemberLookupBlocksAndReportsFailure() {
+        val failure = UnsupportedOperationException("Member lookup unavailable")
+        var reported: Exception? = null
+        assertFalse(allowsGroupChatTrigger(true, 123L, { throw failure }, { reported = it }))
+        assertSame(failure, reported)
+    }
+
+    @Test
+    fun cancellationPropagatesWithoutReportingLookupFailure() {
+        val cancellation = CancellationException("Cancelled")
+        assertSame(cancellation, assertFailsWith<CancellationException> {
+            allowsGroupChatTrigger(true, 123L, { throw cancellation }, { error("Unexpected failure report") })
+        })
+    }
+}