A circular stitching device for a sewing machine includes a body base attachable to a sewing bed or an upper surface of a needle plate, a movable base located on the body base so as to be movable in a predetermined direction, a cloth fixing member including a cloth-fixing pin which is passable through a workpiece cloth and is formed with an engagement portion, and a holder holding a proximal end of the cloth-fixing pin, a cloth-fixing pin support detachably attachable to the movable base thereby to support the cloth fixing member so that the cloth fixing member is detachably attachable thereto, and a locking unit which is located on the cloth-fixing pin support and is disengageably engageable with the engagement portion of the cloth-fixing pin, thereby locking the cloth-fixing pin.