The invention provides a pressure cylinder of a motorcycle engine and belongs to the technical field of engines. By means of the pressure cylinder of the motorcycle engine, the problem of low supercharging efficiency of an existing pressure cylinder is solved. The pressure cylinder of the motorcycle engine comprises a cylinder body and a cylinder cover fixed to the top end of the cylinder body. The cylinder cover is provided with two one-way valve blocks for ventilation of the cylinder body, and the two one-way valve blocks are arranged in a splay shape. The inner space between the two one-way valve blocks is filled with filler. The filler is provided with an air intake hole and an air exhaust hole, wherein opening or closing of the air inlet end of the air intake hole is controlled by the corresponding one-way valve block, and opening or closing of the air outlet end of the air exhaust hole is controlled by the corresponding one-way valve block. The pressure cylinder of the motorcycle engine has high supercharging efficiency.