PURPOSE: To perform deburring automatically by a deburring tool and to discharge burrs by a method in which a work in accurately positioned state is carried into the device while being horizontally held and is reciprocally moved between a discharging part and an operating position.

CONSTITUTION: A work is received in a working room together with a pallet 10 and a tool holder 45 is holizontally lowered. The deburring tools 46, 47 and a cam member 58 of the tool holder 45 are lowered and the cam member 58 clamps the work 1 by pressing. Then, after the tools 46, 47 are lowered, a pair of tools 46, 46 remove the burrs in the holes 3, 4 of the work and the tool 47 removes the burrs in the portion 2 thereof, and then respective burrs 5, 7 are removed. Next, the holizontal tool 52 of a cylinder 51 removes the burrs 8 of the work 1.