A percussion power tool includes a motor (6) located in the tool-housing (4) for driving the output member (12) and the percussion mechanism (10), a chuck (20) for receiving a working tool (22), a locking mechanism (24) for securing the chuck (20) on the output member (12) and including at least one locking member (26) which provides in a locking position thereof, for a formlocking connection between a connection member (30) of the chuck (20) and the output member (12), an adjusting sleeve (34) that prevents, in its blocking position, a radial displacement of the at least one locking member (26) from the locking position and a damping member (56) provided between the output member (12) and the connection member (30) and acting in the axial direction.