The invention relates to a multi-CPU (central processing unit) data communication system and a multi-CPU data communication method for an intelligent substation and belongs to the technical field of network communication of substations of an electric power system. The multi-CPU data communication system comprises at least two CPUs and a communication plug-in NTX, the CPUs are connected with one another via the communication plug-in NTX, an SV (sampled value) signal receiving port and a GOOSE (generic object oriented substation event) signal transceiving port are arranged on the communication plug-in NTX, the SV signal receiving port is used for distributing received SV signals to enable the distributed SV signals to enter the CPUs for processing, and the GOOSE signal transceiving port is used for receiving external GOOSE signals, distributing the GOOSE signals to the CPUs, receiving GOOSE signals sent by the CPUs and transmitting the GOOSE signals from the CPUs to the outside. The multi-CPU data communication system and the multi-CPU data communication method have the advantages that by the aid of the communication plug-in NTX, receiving of SV data, transceiving of the GOOSE signals and interaction among the CPUs via GOOSE information are completed, multi-CPU data communication is achieved, and the multi-CPU data communication system and the multi-CPU data communication method are applicable to multi-CPU devices combined in function and high in intellectualization degree.