To provide a running drive device for a diesel-electric running vehicle in which an operator can operate with the same feeling as a general torque converter/transmission type vehicle.

This device is provided with an engine 11 which is the drive source of plural works and a motor 1 for running supplied an electricity by a generator 12 connected to this engine 11 and the engine speed of the engine 11 can be varried in a prescribed engine speed area according to the operation amount of an acceleration pedal 20. In this constitution, the drive force as well as an engine sound are changed by changing the engine speed of the engine 11 by the operation amount of the acceleration pedal 20 and changing the electric power of the generator 12 by the engine speed. Therefore, an operator can operate with the same feeling as a general torque converter/transmission type vehicle.