Abstract: 5G technology can provide communication solutions for distribution network differential protection technology applications, but the latency and jitter of 5G networks are still unstable, which affects the normal work of distribution network differential protection. Currently, 5G distribution network differential protection applications lack the means to monitor the performance of end-to-end communication links in real time and accurately. This paper proposes a probe technology for network performance monitoring of specific message tagging time information for differential protection in 5G terminals, and verifies the feasibility of applying network probe technology in differential protection business based on the networking scheme of soft slicing and hard slicing of 5G virtual private network, respectively, to provide a guarantee for the wide application of 5G technology in power business.