Diesel locomotive, supplied by diesel generate AC, AC current through tract transducer convert into 3 phase to supply two common3 phase traction motor, each motor rotor through coupling drive reduction gearbox, through secondary gear reduce box transmission to the wheel-axle, thus tract the locomotive. Diesel locomotive main structure is divided into the body, walking device, air braking system, drive system, electric brake mode and brake resistance, sound purification system, steering control system, air compressor system, etc.