Belt buckle

A belt buckle with a watch unit comprising a dressed plate, a lock fitting secured to one edge of the dressed plate at the rear side thereof for fixing one end of a belt, a pin secured to the other edge of the dressed plate at the rear side for clamping the belt by inserting it in one of a plurality of clamp holes provided at the other end portion of the belt, a rotatable plate pivotally provided to the edge of the dressed plate at the lock fitting side, and a watch unit embedded in the rotatable plate, the rotatable plate comprises a snap clamp, the snap clamp comprises a ball provided to the upper and side edge of the rotatable plate through a second spring in such a manner that a part of the ball is projected from the side edge of the rotatable plate in the closed condition thereof, and a recess provided at the upper and side edge of the dressed plate to receive the projected part of the ball in the closed condition of the rotatable plate.