The invention discloses a general disassembling and assembling tool for a braking air cylinder and belongs to the technical field of disassembling and assembling tools for railway vehicles. The general disassembling and assembling tool comprises an end face positioning plate, an adjustable positioning block, a push rod seat, a screw rod, a three-phase asynchronous motor, a turbine worm reducer, aguide rail and a rack. The end face positioning plate is fixed to one end of the rack, and the guide rail is arranged on the table top of the rack. The push rod seat is mounted on the guide rail and can move back and forth along the guide rail. One end of the push rod seat is the threaded end connected with the screw rod in a screwed mode. The screw rod and the turbine worm reducer are connected,and the turbine worm reducer is connected with the three-phase asynchronous motor. The push rod seat is provided with a clamping plate used for matching use with the end face positioning plate to serve as an axial clamp of the braking air cylinder. The adjustable positioning block serves as a circumferential positioning clamp of the braking air cylinder, is perpendicular to the end face positioning plate, and is used for height adjustment of the braking air cylinder. The general disassembling and assembling tool can conduct general disassembling on the braking air cylinders of different types.