Abstract: Nowadays, more and more new energy vehicle charging pile testers provide the function of time calibration, but this function has not yet achieved traceability, and the accuracy of the downward transmission time cannot be guaranteed. This paper uses the remote time and frequency traceability system that can be traced to UTC (NIM) in real-time to achieve accurate time traceability of the new energy vehicle charging pile tester. At the same time, according to different time differences and time accuracy requirements, different methods are used to achieve traceability up to the millisecond level with an expanded uncertainty of 0.18 ms.