The present disclosure discloses a vehicle-mounted type back scattering inspection system. The back scattering imaging device has a vehicle-mounted working state and a ground working state, and in the vehicle-mounted working state, the back scattering imaging device performs inspection work in the carriage; in the ground working state, the back scattering imaging device performs the inspection work on the ground at the outside of the carriage; and the back scattering imaging device is separately arranged relative to the carriage and is movable between the carriage and the ground to switch between the vehicle-mounted working state and the ground working state.