The invention discloses a mechanical interlocking type parking brake for a railway vehicle. The mechanical interlocking type parking brake comprises a brake cylinder assembly and a mechanical interlocking mechanism, wherein the brake cylinder assembly comprises a cylinder body, a piston, a piston rod and a release spring; the mechanical interlocking mechanism comprises a locking base also used as a cylinder cover, the piston rod extends out of the locking base to be connected with a regulating shaft of a vehicle brake device, the locking base is internally provided with a locking nut rotating along the circumferential direction of the piston rod and a locking shaft sleeve moving along the axial direction of the piston rod, a rest spring by which tow end faces of the locking shaft sleeve and the piston rod are in butt joint is arranged between the locking shaft sleeve and the piston rod, a friction pair meshed face is formed at the joint of the end faces of the locking shaft sleeve and the piston rod, and a compressed air flange connector is connected with a vehicle main air pipeline is arranged in the side wall of the locking base, and is communicated with one side of the locking shaft sleeve, which is close to one side of the locking nut. The mechanical interlocking type parking brake is used for combining travelling brake and parking brake of the vehicle into a whole, is capable of automatically starting the parking brake and keeping a brake force until the brake release is started if necessary, and has the characteristics of uniform brake force, short parking brake time, safety in operation of the vehicle, and the like.