The present invention relates to a handpiece having a dust discharge structure. The handpiece having a dust discharge structure includes a case part having a cylindrical shape to be gripped by a hand； a pair of rear bearings inserted into an inner side of the case part to be spaced part from each other； a motor provided between the rear bearings, and having a driving shaft that transfers a rotating force extended at both sides of the motor so that the motor is axially rotated at the rear bearing； a power supply connected to a rear direction of the motor to supply a current to the motor； a spindle part connected to a forward direction of the driving shaft of the motor to transfer the rotating force of the motor, and wherein a connection shaft, a rotating shaft, and a chuck housing are sequentially connected thereto in the forward direction； a pair of front bearings coupled with both sides of the spindle part, and provided therein the spindle part which facilitates axial rotation； a collet chuck that is cylindrically formed at the chuck housing of the spindle part so that a forward direction thereof protrudes, the inner side of which is formed to allow passage, having multiple cutting grooves radially spaced apart from each other to be horizontally cut in the forward direction, and including a reinforcing portion inclined outward and upward in the forward direction of the cutting groove and formed therein with one end horizontally extending； and a front case formed to enclose a forward outer peripheral portion of the collet chuck, an inner side of the case being formed to allow passage so that one side is coupled with a forward direction of the case part, and wherein multiple exhaust holes are formed through an outer peripheral portion.본 발명은 분진 토출구조를 갖는 핸드피스에 관한 것으로 원통형으로 형성되어 손으로 파지 가능하도록 구성되는 케이스부와, 상기 케이스부의 내측에 삽입되어 구비되며, 각각 이격되어 한쌍으로 구비되는 리어베어링과, 상기 리어베어링의 사이에 구비되며, 양측에는 각각 회전력을 전달하는 구동축이 연장형성되어 리어베어링에 축 회전 가능하도록 결합되는 모터와, 상기 모터의 후방에 연결 구비되어 모터에 전류를 공급하는 전원부와, 상기
