diff --git a/cli.go b/cli.go
index c5f4dc3..2b422f9 100644
--- a/cli.go
+++ b/cli.go
@@ -3,6 +3,7 @@ package manager
 import (
 	"context"
 	"log"
+	"sync"
 
 	"git.godopu.net/lab/etri-smartfarm-poc-controller-serial/puserial"
 	"github.com/rjeczalik/notify"
@@ -21,13 +22,15 @@ func init() {
 	devWithUUID := map[string]*_device{}
 	devWithIface := map[interface{}]*_device{}
 	chanForSync := map[string]chan map[string]interface{}{}
+	var mutex = sync.Mutex{}
 
 	_managerObj = &_manager{
 		devicesWithUUID:  devWithUUID,
 		devicesWithIface: devWithIface,
 		chanForSync:      chanForSync,
-		SyncListener:     &SyncHandler{devices: devWithUUID, chanForSync: chanForSync},
-		RecvListener:     &RecvHandler{devices: devWithIface, chanForSync: chanForSync},
+		mutex:            &mutex,
+		SyncListener:     &SyncHandler{devices: devWithUUID, chanForSync: chanForSync, mutex: &mutex},
+		RecvListener:     &RecvHandler{devices: devWithIface, chanForSync: chanForSync, mutex: &sync.Mutex{}},
 	}
 
 	registerHandleFunc = nil
diff --git a/listener.go b/listener.go
index d1a3643..f2e5fb2 100644
--- a/listener.go
+++ b/listener.go
@@ -4,10 +4,12 @@ import (
 	"encoding/json"
 	"fmt"
 	"log"
+	"sync"
 )
 
 type SyncHandler struct {
 	devices     map[string]*_device
+	mutex       *sync.Mutex
 	chanForSync map[string]chan map[string]interface{}
 }
 
@@ -67,8 +69,10 @@ func (sh *SyncHandler) Handle(e Event) {
 
 		_, ok := sh.chanForSync[device.IfaceName]
 		if ok {
+			sh.mutex.Lock()
 			close(sh.chanForSync[device.IfaceName])
 			delete(sh.chanForSync, device.IfaceName)
+			sh.mutex.Lock()
 		}
 		chanForSync := make(chan map[string]interface{})
 		sh.chanForSync[device.IfaceName] = make(chan map[string]interface{})
@@ -76,23 +80,26 @@ func (sh *SyncHandler) Handle(e Event) {
 		for state := range chanForSync {
 
 			if compareMap(origin, state) {
+				sh.mutex.Lock()
 				close(sh.chanForSync[device.IfaceName])
 				delete(sh.chanForSync, device.IfaceName)
+				sh.mutex.Lock()
 				return
 			}
 			log.Println("wrong: ", state)
 			log.Println("resend: ", origin)
 			err := encoder.Encode(origin)
 			if err != nil {
-				log.Println("sync routine is died")
 				return
 			}
 		}
+		log.Println("sync routine is died")
 	}()
 }
 
 type RecvHandler struct {
 	devices     map[interface{}]*_device
+	mutex       *sync.Mutex
 	chanForSync map[string]chan map[string]interface{}
 	next        EventHandler
 }
@@ -110,7 +117,9 @@ func (rh *RecvHandler) Handle(e Event) {
 	}
 
 	device.states = param
+	rh.mutex.Lock()
 	channel, ok := rh.chanForSync[device.IfaceName]
+	rh.mutex.Unlock()
 	if ok {
 		channel <- device.states
 	}
diff --git a/manager.go b/manager.go
index 0fa71a4..cd410c5 100644
--- a/manager.go
+++ b/manager.go
@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"io"
 	"log"
+	"sync"
 
 	"github.com/jacobsa/go-serial/serial"
 )
@@ -14,6 +15,7 @@ type _manager struct {
 	devicesWithUUID  map[string]*_device
 	devicesWithIface map[interface{}]*_device
 	chanForSync      map[string]chan map[string]interface{}
+	mutex            *sync.Mutex
 	RegisterListener EventHandler
 	SyncListener     EventHandler
 	RecvListener     EventHandler
@@ -127,5 +129,5 @@ func (m *_manager) onRecv(key interface{}, params map[string]interface{}) {
 }
 
 func (m *_manager) addRecvListener(h EventHandler) {
-	m.RecvListener = &RecvHandler{next: h, devices: m.devicesWithIface, chanForSync: m.chanForSync}
+	m.RecvListener = &RecvHandler{next: h, devices: m.devicesWithIface, chanForSync: m.chanForSync, mutex: m.mutex}
 }