The invention discloses a wheelbase-variable rolling device. The wheelbase-variable rolling device comprises hub motor wheels, suspension brackets, a supporting frame and a telescopic hydraulic cylinder, wherein the suspension brackets are connected with the hub motor wheels, a longitudinal slider is installed on each suspension bracket, the telescopic hydraulic cylinder is installed on the supporting frame, a telescoping rod of the telescopic hydraulic cylinder is provided with a longitudinal guide rail, and each longitudinal slider is matched with a longitudinal sliding rail in a sliding mode; a driving device comprises first self-driven wheels, the supporting frame is provided with self-driven wheel rolling platforms, the first self-driven wheels are located on the upper surfaces of theself-driven wheel rolling platforms respectively, second self-driven wheels are located on the lower surfaces of the self-driven wheel rolling platforms respectively, one end of a telescopic sleeve is fixedly connected to one sides of the longitudinal sliders, the other end of the telescopic sleeve is connected to connecting brackets, each connecting bracket is provided with two connection ends,one end of each connecting bracket is connected with the corresponding first self-driven wheel, and the other end of each connecting bracket is connected with the corresponding second self-driven wheel. The wheelbase-variable rolling device has the advantages that the structure is simple, and the axial spacing and the vertical spacing of wheels can be changed.