A slide rail mechanism includes a rail member, a supporting frame and a bracket. The supporting frame is movable relative to the rail member and the bracket. The bracket includes a side wall and at least one mounting member adjacent to the side wall. The at least one mounting member configured to pass through a mounting hole of a post. When the supporting frame is moved relative to the bracket from a first position to a second position, the supporting frame is configured to drive the at least one mounting member to move relative to the side wall.