A firing mechanism with safety device for firearms, especially sport and hunting rifles and shotguns, with at least one barrel and a firing pin associated therewith and operable by way of a striker member in that the member is movable into an uncocked position, under the influence of the force of a compressed spring, against the firing pin after a trigger lever locking the striker member in a cocked position has been placed into a release position, and with at least one trigger with an associated rocker arm. In order to secure the firearm against unintended firing of shots due to external impact effects, the striker member is fashioned as a slide and is displaceable in the longitudinal direction from a rearward cocked position into a forward uncocked position. The trigger lever has an angled, curved, or like configuration and is arranged at the striker member so that it extends in the longitudinal direction and is pivotable about an axial support in such a way that, in the cocked position, the rear end of the trigger lever is secured by the rocker arm and the front end of the trigger lever rests in the forward direction on a stop fixedly formed within the frame and locks the striker member in the cocked position; this locking action being releasable by freeing the rear end of the trigger lever by way of the trigger-operated rocker arm and pivoting the trigger lever in such a way that the support of its front end at the stop is eliminated.