diff --git a/core/connection.go b/core/connection.go
index 5b5a26d..630572a 100644
--- a/core/connection.go
+++ b/core/connection.go
@@ -40,9 +40,11 @@ type (
 		session *session.Session // Session
 		ngin    *engine          // engine
 
-		conn    net.Conn // low-level conn fd
-		status  int32    // 连接状态
-		lastMid uint64   // 最近一次消息ID
+		status int32         // 连接状态
+		conn   net.Conn      // low-level conn fd
+		packer packet.Packer // 封包、拆包器
+
+		lastMid uint64 // 最近一次消息ID
 		// TODO 考虑独立出去作为一个中间件
 		lastHeartbeatAt int64 // 最近一次心跳时间
 
@@ -59,9 +61,11 @@ type (
 
 func newConn(server *engine, conn net.Conn) *Connection {
 	r := &Connection{
-		conn:   conn,
-		ngin:   server,
+		ngin: server,
+
 		status: StatusStart,
+		conn:   conn,
+		packer: server.packerFn(),
 
 		lastHeartbeatAt: time.Now().Unix(),
 
@@ -189,7 +193,7 @@ func (r *Connection) write() {
 			}
 
 			// packet pack data
-			p, err := r.ngin.packer.Pack(data.header, data.payload.([]byte))
+			p, err := r.packer.Pack(data.header, data.payload.([]byte))
 			if err != nil {
 				log.Error(err.Error())
 				break
@@ -222,13 +226,13 @@ func (r *Connection) read() {
 			return
 		}
 
-		if r.ngin.packer == nil {
+		if r.packer == nil {
 			log.Errorf("unexpected error: packer is nil")
 			return
 		}
 
 		// warning: 为性能考虑，复用slice处理数据，buf传入后必须要copy再处理
-		packets, err := r.ngin.packer.Unpack(buf[:n])
+		packets, err := r.packer.Unpack(buf[:n])
 		if err != nil {
 			log.Error(err.Error())
 		}
diff --git a/core/engine.go b/core/engine.go
index dda6275..0b82be6 100644
--- a/core/engine.go
+++ b/core/engine.go
@@ -42,7 +42,7 @@ type (
 
 		pipeline Pipeline // 消息管道
 
-		packer     packet.Packer        // 封包、拆包器
+		packerFn   packet.NewPackerFunc // 封包、拆包器
 		processor  Processor            // 数据包处理器
 		serializer serialize.Serializer // 消息 序列化/反序列化
 
diff --git a/core/server.go b/core/server.go
index d4af948..2bf5e56 100644
--- a/core/server.go
+++ b/core/server.go
@@ -107,9 +107,9 @@ func WithRouter(router Router) RunOption {
 	}
 }
 
-func WithPacker(packer packet.Packer) RunOption {
+func WithPacker(fn packet.NewPackerFunc) RunOption {
 	return func(server *Server) {
-		server.ngin.packer = packer
+		server.ngin.packerFn = fn
 	}
 }
 
diff --git a/core/server_test.go b/core/server_test.go
index 0240645..8b180cb 100644
--- a/core/server_test.go
+++ b/core/server_test.go
@@ -15,7 +15,9 @@ func TestServer(t *testing.T) {
 		Name:     "N-Net",
 		Mode:     DevMode,
 	},
-		WithPacker(packet.NewNNetPacker()),
+		WithPacker(func() packet.Packer {
+			return packet.NewNNetPacker()
+		}),
 		WithSerializer(nil),
 		WithHeartbeatInterval(time.Hour),
 		WithProcessor(NewNNetProcessor()),
diff --git a/packet/packet.go b/packet/packet.go
index 41d8a80..cd90812 100644
--- a/packet/packet.go
+++ b/packet/packet.go
@@ -16,4 +16,6 @@ type (
 		// Unpack 解包
 		Unpack(data []byte) ([]IPacket, error)
 	}
+
+	NewPackerFunc func() Packer
 )