diff --git a/packages/koishi-core/src/app.ts b/packages/koishi-core/src/app.ts
index 967f304b76..703f2f70a6 100644
--- a/packages/koishi-core/src/app.ts
+++ b/packages/koishi-core/src/app.ts
@@ -359,6 +359,9 @@ export class App extends Context {
         const group = await this.database.observeGroup(meta.groupId, Array.from(groupFields))
         Object.defineProperty(meta, '$group', { value: group, writable: true })
 
+        // emit attach event
+        this.emitEvent(meta, 'attach-group', meta)
+
         // ignore some group calls
         const isAssignee = !group.assignee || group.assignee === this.selfId
         const noCommand = group.flag & GroupFlag.noCommand
@@ -377,6 +380,7 @@ export class App extends Context {
 
       // emit attach event
       this.emitEvent(meta, 'attach', meta)
+      this.emitEvent(meta, 'attach-user', meta)
 
       // ignore some user calls
       if (user.flag & UserFlag.ignore) return
diff --git a/packages/koishi-core/src/context.ts b/packages/koishi-core/src/context.ts
index 024916dc9c..f5b32ca364 100644
--- a/packages/koishi-core/src/context.ts
+++ b/packages/koishi-core/src/context.ts
@@ -294,7 +294,8 @@ export interface EventMap {
   'lifecycle/connect' (meta: Meta<'meta_event'>): any
   'before-user' (fields: Set<UserField>, argv: ParsedCommandLine): any
   'before-group' (fields: Set<GroupField>, argv: ParsedCommandLine): any
-  'attach' (meta: Meta<'message'>): any
+  'attach-user' (meta: Meta<'message'>): any
+  'attach-group' (meta: Meta<'message'>): any
   'send' (meta: Meta<'send'>): any
   'before-send' (meta: Meta<'send'>): any
   'before-command' (argv: ParsedCommandLine): any
@@ -315,6 +316,9 @@ export interface EventMap {
   'connect' (): any
   'before-disconnect' (): any
   'disconnect' (): any
+
+  // TODO: deprecated events
+  'attach' (meta: Meta<'message'>): any
 }
 
 export type Events = keyof EventMap