diff --git a/components/bt/bluedroid/btif/bta_dm_co.c b/components/bt/bluedroid/btif/bta_dm_co.c
index 38002fae0..291db9e3d 100644
--- a/components/bt/bluedroid/btif/bta_dm_co.c
+++ b/components/bt/bluedroid/btif/bta_dm_co.c
@@ -502,7 +502,7 @@ void bta_dm_co_ble_set_rsp_key_req(UINT8 rsp_key)
 void bta_dm_co_ble_set_max_key_size(UINT8 ble_key_size)
 {
 #if (SMP_INCLUDED == TRUE)
-    if(ble_key_size >= 7 && ble_key_size >= 16) {
+    if(ble_key_size >= BTM_BLE_MIN_KEY_SIZE && ble_key_size <= BTM_BLE_MAX_KEY_SIZE) {
         bte_appl_cfg.ble_max_key_size = ble_key_size;
     } else {
         APPL_TRACE_ERROR("%s error:Invalid key size value, key_size =%d",__func__, ble_key_size);
diff --git a/components/bt/bluedroid/stack/include/btm_api.h b/components/bt/bluedroid/stack/include/btm_api.h
index 4af3a4863..d4ee7b473 100644
--- a/components/bt/bluedroid/stack/include/btm_api.h
+++ b/components/bt/bluedroid/stack/include/btm_api.h
@@ -1416,6 +1416,7 @@ typedef UINT8 tBTM_IO_CAP;
 #define BTM_BLE_INITIATOR_KEY_SIZE 15
 #define BTM_BLE_RESPONDER_KEY_SIZE 15
 #define BTM_BLE_MAX_KEY_SIZE       16
+#define BTM_BLE_MIN_KEY_SIZE       7
 
 typedef UINT8 tBTM_AUTH_REQ;