Abstract: The present invention concerns a method for operating and arrangement of a pneumatic piston engine. The pneumatic piston engine (1) includes a cylinder (2) including a piston (3) kinematically joined via a crank (4) to a crankshaft (5) and a working chamber (6) supplied with a means (7) for supply of compressed air and a means (8) for exhaust of air. The starting of supply of compressed air is realized while the piston (3) is in the region within the range from 40° before top dead center to 25° after top center by angle of rotation o the crank of the crankshaft depending on engine speed, and the ending of supply is realized while the piston (3) is in the region within the range from 0° to 90° after top dead center by angle of rotation of the crank of the crankshaft. In particular case when engine speed is 2.