With the large-scale deployment of Optical Transport Network/Packet-enhanced Optical Transport Network（OTN/POTN）technology

the problem of bearing frequency and time synchronization signal in OTN/POTN occurs.This paper proposes a test method based on 1588+SyncE synchronous network.Through the configuration of additional Optical Supervisory Channel（OSC）board and clock interface board in source OTN/POTN equipment

and the point by point method was used for the synchronous signal to be tested in a local loopback mode.This scheme solves the problem of measurement error due to remote testing

while removing the restriction of test source and test reference point

and can be tested at any node of the OTN/POTN system according to actual needs

reduce the cost of testing.