Abstract: A belt and buckle assembly in which the clamping plate which is turned about a transverse pivot pin at one end of the buckle has two perpendicular teeth and is supported on a torsional spring; the belt has two longitudinal series of sloping teeth and a plurality of longitudinal rows of spaces alternatively disposed at a back side thereof near the tail; the teeth of the clamping plate allow the sloping teeth of the belt to pass forward and stop them from backward movement; the belt is released from the buckle when the clamping plate is moved downward to compress the torsional spring and to shift the teeth into the longitudinal rows of spaces.