Abstract: A single-blow pneumatic percussive tool includes a hollow cylindrical casing (1) having inlet and outlet ports (2, 3). A hammer piston (4) mounted in the casing (1) divides the interior space of the casing (1) into lower and upper chambers (5,6). A working tool (7) is mounted in the casing (1) on the side of the lower chamber (5). A handle (9) having passages and an air distribution device (8) is mounted in the upper part of the casing (1). A sleeve (12) with ports (13) is mounted on the casing (1) to define a space (14) therewith. An air distribution sleeve (15) is axially biased by a spring mounted in the space (14). The outlet ports (3) of the casing (1) are aligned with the ports (13) of the sleeve (12). The air distribution sleeve (15) has radial ports and recesses (17) which are aligned with the radial ports ( 16) on both surfaces of the air distribution sleeve (15). At least one passage (18) is made in the hammer piston (47) which is biased by spring on the side of the lower chamber (5).