Rear wheel disc type parking brake

The invention discloses a rear wheel disc type parking brake. The rear wheel disc type parking brake comprises a brake disc, a brake wheel cylinder, a piston, a thrust disc, thrust columns, a drivingpiece and a friction plate, and an open oil cavity is formed in one end of the brake wheel cylinder; the piston is arranged in the oil cavity in an axial sliding manner; the thrust disc is rotationally arranged in a containing cavity, the driving piece is connected with the thrust disc so as to drive the thrust disc to rotate, and arc-shaped spiral grooves are formed in the end face, away from thepiston, of the thrust disc in a concave manner; and one ends of the thrust columns are fixedly connected with the end face of the friction plate, and the other ends of the thrust columns abut againstthe interiors of the arc-shaped spiral grooves. Compared with the prior art, the rear wheel disc type parking brake solves the problems that a disc drum type parking brake is low in braking capacityand cannot meet the requirem