The invention discloses a rampway auxiliary skid-resistant device for truck and an installation and use method, and relates to the field of skid-resistant equipment. The rampway auxiliary skid-resistant device comprises a fixing bracket, a rotating bracket, a pair of wedge blocks, an electric air cylinder, a connecting rod, a power supply and a switch. The rotating bracket is of a symmetrical structure, and comprises a large transverse rod, a large longitudinal rod, a pair of small longitudinal rods and a pair of small transverse rods; the wedge blocks are correspondingly connected with the outer ends of the small transverse rods; a pair of supporting plates are arranged on the rear side of the fixing bracket; shaft holes are formed in the supporting plates; the large transverse rod is arranged in the shaft holes in a rotating connecting mode; the electric air cylinder is arranged at the center of the top of the fixing bracket; a piston rod of the electric air cylinder extends to the rear side; the electric air cylinder is in electric connection with the power supply and the switch correspondingly; and one end of the connecting rod is hinged to the top end of the large longitudinalrod, and the other end of the connecting rod is hinged to the head portion of the piston rod. The rampway auxiliary skid-resistant device is reasonable in structural design, and enables the truck tobe safely parked on a rampway when mounted on the truck.