The invention relates to a real-time synchronization method of the dynamic performance test system of fuel cell vehicles, which is used for the clock synchronization and the data synchronization of communication networks of the dynamic performance test system of the fuel cell vehicles. The method comprises steps as follows: (1) the communication network of the dynamic performance test system of the fuel cell vehicle is established; (2) clocks of all the device nodes in the communication network are synchronized by using the NTP (Network Time Protocol) network synchronization method; and (3) the hardware and software of the communication network are configured separately, synchronous timing rules are made, and thus the data of the entire communication network are synchronized. Compared with the prior art, the invention has the characteristics of overall planning, a plurality of communication protocols, capacity of meeting load requirements, distributed network and the like.