The invention relates to a device for detecting and counting live bullet shots, blank shots and dry-firing actuation of the striker for all types of semi-automatic or automatic weapons, said device being able to discriminate between said three events and comprising: an electronic circuit (5); a first sensor for detecting a movement of a part (2) of the weapon preceding a potential live bullet shot or blank shot; and a second sensor (6) for measuring recoil acceleration when the live bullet shot or blank shot has been fired.