The watch striking mechanism (1) includes a gong, which is fixed via one end thereof to a gong-carrier integral with a plate, a hammer rotatably mounted on the plate to strike the gong at determined times, a damper counter-spring (5) for keeping the hammer away from the gong in an idle mode, and a drive spring (3) for the hammer. The drive spring includes an end (3b) fixed to the plate and an end (3a) that is free to move. The spring can be wound so that the free end (3a) of the spring drives the hammer (2) against the gong (21) in a strike mode to produce an acoustic sound. The striking mechanism includes means (10) for actuating the damper counter-spring (5) in a strike mode with a time lag after the hammer (2) strikes the gong, so that after the hammer strikes the gong, the counter-spring pushes said hammer towards an idle position. The actuating means includes a stop member mounted on the damper counter-spring to be actuated via the drive spring when in action just after the hammer strikes the gong.