The Chinese locomotive remote monitoring and diagnosis system (CMD system) is one of the basic subsystems of the railway locomotive management information system, which can realize locomotive positioning, dynamically track the "human-vehicle map", and conduct condition monitoring, remote diagnosis and troubleshooting of locomotive equipment in transit. The system consists of a vehicle subsystem (model YLDP-1), a data transmission subsystem, and a ground integrated application subsystem. Realization of remote monitoring and fault diagnosis functions for locomotive operation. At the same time, CMD system integrates with various external information systems such as quality information database, car number identification system, transportation safety system, maintenance system, preparation system, LKJ analysis software, TCMS ground analysis software, 6A system ground analysis software, locomotive electronic history system, etc. The information of LKJ, TCMS, 6A, etc. is integrated and data mined through the ground integrated application subsystem to provide powerful data support for transportation, management and maintenance.