diff --git a/ft/modbus_tcp_test.robot b/ft/modbus_tcp_test.robot
index 901a9a1d..36b21bed 100644
--- a/ft/modbus_tcp_test.robot
+++ b/ft/modbus_tcp_test.robot
@@ -154,6 +154,22 @@ Read all type tag with same slave id in input register and input, it should be s
 	${input_bit_4}    input_bit_4    ${modbus_tcp_node}    Compare Tag Value As Int    0
 	${input_bit_5}    input_bit_5    ${modbus_tcp_node}    Compare Tag Value As Int    0	
 
+Read in sync mode, it should fail.
+	${res}=	Add Group  ${modbus_tcp_node}  group  100
+	Check Response Status  ${res}  200
+	Check Error Code  ${res}  ${NEU_ERR_SUCCESS}
+
+	${res}=	Add Tags  ${modbus_tcp_node}  group  ${input_register_int16},${input_register_uint16},${input_register_int32},${input_register_uint32},${input_register_float},${input_register_string},${input_register_bit}
+	Check Response Status  ${res}  200
+	Check Error Code  ${res}  ${NEU_ERR_SUCCESS}
+
+	Sleep 	290ms
+	${res}=	Read Tags  ${modbus_tcp_node}  group  true
+	Check Response Status  ${res}  200
+	Check Response Status  ${res}  ${NEU_ERR_PLUGIN_NOT_SUPPORT_READ_SYNC}
+
+	[Teardown]	Del Group  ${modbus_tcp_node}  group
+
 Read some tags at time, it will be success.
 	[Template] 	Read some ${tags} from ${node}, it will be success.
 	${input_register_int16},${input_register_uint16},${input_register_int32},${input_register_uint32},${input_register_float},${input_register_string},${input_register_bit} 	${modbus_tcp_node}
diff --git a/ft/resource/api.resource b/ft/resource/api.resource
index 446d0f55..9e909e71 100644
--- a/ft/resource/api.resource
+++ b/ft/resource/api.resource
@@ -197,8 +197,8 @@ Del Tags
   [RETURN]            ${res}[0]
 
 Read Tags
-  [Arguments]         ${node}              ${group}
-  POST                /api/v2/read            {"node": "${node}", "group": "${group}"}
+  [Arguments]         ${node}              ${group}                      ${sync}=false
+  POST                /api/v2/read            {"node": "${node}", "group": "${group}", "sync": ${sync}}
   ${res} =            Object  response body
   [RETURN]            ${res}[0]
 
diff --git a/ft/resource/error.resource b/ft/resource/error.resource
index 5619f20f..16844942 100644
--- a/ft/resource/error.resource
+++ b/ft/resource/error.resource
@@ -95,5 +95,6 @@ ${NEU_ERR_PLUGIN_NOT_FOUND}                     3014
 ${NEU_ERR_PLUGIN_DEVICE_NOT_RESPONSE}           3015
 ${NEU_ERR_PLUGIN_NOT_SUPPORT_TEMPLATE}          3016
 ${NEU_ERR_PLUGIN_NOT_SUPPORT_WRITE_TAGS}        3017
+${NEU_ERR_PLUGIN_NOT_SUPPORT_READ_SYNC}         3018
 
 ${NEU_ERR_MQTT_SUBSCRIBE_FAILURE}               4010