The invention relates to the technical field of vehicle engineering, in particular to a heavy-load vehicle in-compartment moving device which comprises a platform main structure, a power system, a jacking system and a control system. The platform main structure comprises a main beam and an outer frame arranged on the main beam, and an electric appliance cabin is arranged between the main beam and the outer frame; the power system comprises a motor driving set, a coupler connected with the motor driving set and a Mecanum wheel connected with the coupler; the jacking system is a hydraulic jack which is arranged on the platform main structure; the control system comprises a traveling controller, an operation controller, a motor driving module, a power source management device and a remote controller. The heavy-load vehicle in-compartment moving device is controlled by adopting CAN (controller area network) bus technology of all-in technology, the Mecanum wheel realizes omnibearing moving, working efficiency is high, and response speed is high; a double-insurance braking mode of wireless remote control and own scram braking is adopted, so that scram braking can be realized in emergency, and safety is guaranteed.