A buckle comprising: a first connector member including a first base, a first plate extending forward from the first base, a plurality of connecting grooves formed on the first plate, a locking portion formed at one side of each connecting groove, and a first channel formed at a rear portion of the first base to couple a first strap; a second connector member including a second base, a second plate extending forward from the second base, a plurality of connecting hooks protruding from the second plate to be inserted into the corresponding connecting groove of the first connector member and be movable in a lateral direction in an insertion state, with a front end of the respective connecting hooks being provided with a locking shoulder, and a second channel formed at a rear portion of the second base to couple a second strap; and a fastening means including a first locking protrusion protruding from one end portion of the first connector member which faces a corresponding surface of the second connector member, and a second locking protrusion protruding from a resilient piece provided at a center portion of the second connector member which corresponds to the first locking protrusion, in which the first locking protrusion and the second locking protrusion are engaged when the first connector member and the second connector member are laterally moved in an opposite direction, and are disengaged by operation of the resilient piece, wherein the buckle is connected or disconnected by moving the first connector member and the second connector member in a lateral direction in a contact state. a first connector member including a first base, a first plate extending forward from the first base, a plurality of connecting grooves formed on the first plate, a locking portion formed at one side of each connecting groove, and a first channel formed at a rear portion of the first base to couple a first strap; a second connector member including a second base, a second plate extending forward from the second base, a plurality of connecting hooks protruding from the second plate to be inserted into the corresponding connecting groove of the first connector member and be movable in a lateral direction in an insertion state, with a front end of the respective connecting hooks being provided with a locking shoulder, and a second channel formed at a rear portion of the second base to couple a second strap; and a fastening means including a first locking protrusion protruding from one end portion of the first connector member which faces a corresponding surface of the second connector member, and a second locking protrusion protruding from a resilient piece provided at a center portion of the second connector member which corresponds to the first locking protrusion, in which the first locking protrusion and the second locking protrusion are engaged when the first connector member and the second connector member are laterally moved in an opposite direction, and are disengaged by operation of the resilient piece, wherein the buckle is connected or disconnected by moving the first connector member and the second connector member in a lateral direction in a contact state.