The invention belongs to a locomotive transport monitoring system and method and discloses an automatic power supply signal electrical blocking system and method for an electric locomotive. Erected wires of the blocking system are in segmental arrangement, an insulator is arranged between every two segments of the erected wires, signal lights are arranged at positions of the insulators respectively, and erected wire controllers are arranged in front and rear sections of the insulators or on a mine locomotive. An erected wire controller is connected between every segment of the erected wires and a direct-current power line and used for connection or disconnection of a direct-current power source on the corresponding erected wires. The blocking method includes: a base station sends block signals to a ground control computer through a gateway, and the ground control computer sends control instructions for changing signal light states; when block conditions are serious, the mine locomotive is powered off to disable other vehicles to enter block sections to forcedly forbid traveling. The locomotive transport monitoring system and the method have advantages that due to simultaneous electrical and signal blocking, electrical blocking and signal blocking synchronization is realized, accidentally running the red light due to exhaustion of a locomotive driver can be avoided, and safety accidents caused by ambiguous onsite driving logical laws are avoided.