diff --git a/message.go b/message.go
index 7a2ded4..20bd9a2 100644
--- a/message.go
+++ b/message.go
@@ -91,26 +91,15 @@ func (m *Message) SenderInGroup() (*User, error) {
 		}
 		return nil, errors.New("can not found sender from system message")
 	}
-	group, err := m.Sender()
+	user, err := m.Sender()
 	if err != nil {
 		return nil, err
 	}
-	if group.IsFriend() {
-		return group, nil
+	if user.IsFriend() {
+		return user, nil
 	}
-	// 如果群聊的群成员是空的, 则从服务器获取
-	if group.MemberList.Count() == 0 {
-		// 更新群详情
-		if err = group.Detail(); err != nil {
-			return nil, err
-		}
-	}
-	users := group.MemberList.SearchByUserName(1, m.senderInGroupUserName)
-	if users == nil {
-		return nil, ErrNoSuchUserFoundError
-	}
-	users.init(m.Bot.self)
-	return users.First(), nil
+	group := &Group{user}
+	return group.SearchMemberByUsername(m.senderInGroupUserName)
 }
 
 // Receiver 获取消息的接收者
diff --git a/relations.go b/relations.go
index f7c2d84..1240836 100644
--- a/relations.go
+++ b/relations.go
@@ -195,6 +195,28 @@ func (g *Group) Rename(name string) error {
 	return g.Self.RenameGroup(g, name)
 }
 
+// SearchMemberByUsername 根据用户名查找群成员
+func (g *Group) SearchMemberByUsername(username string) (*User, error) {
+	if g.MemberList.Count() == 0 {
+		if _, err := g.Members(); err != nil {
+			return nil, err
+		}
+	}
+	members := g.MemberList.SearchByUserName(1, username)
+	// 如果此时本地查不到, 那么该成员可能是新加入的
+	if members.Count() == 0 {
+		if _, err := g.Members(); err != nil {
+			return nil, err
+		}
+	}
+	// 再次尝试获取
+	members = g.MemberList.SearchByUserName(1, username)
+	if members.Count() == 0 {
+		return nil, ErrNoSuchUserFoundError
+	}
+	return members.First(), nil
+}
+
 type Groups []*Group
 
 // Count 获取群组数量