The invention belongs to the technical field of electronic device manufacturing, and particularly relates to a circuit board processing method. The circuit board processing method comprises the following steps of A, material opening, in which a large copper plate is cut into a plurality of small copper plates; B, inner-layer film formation, in which a dry film is attached onto the copper plate andis exposed by ultraviolet ray; C, internal etching; the exposed copper plate is placed in an alkali solution; D, brownization, composition and plate pressing to obtain a substrate; and E, drilling, in which a drilling device is arranged to drill, wherein the drilling device comprises a rack, a drilling mechanism and a dust removal mechanism, the drilling mechanism comprise a motor, a rotation wheel, a sliding block, a mobile rack, a support block, a sliding rod and a drilling head, and the dust removal mechanism comprises a main oscillating rod, a straight rod, a dust removal piston and a dust removal chamber. With the circuit board processing method disclosed by the technical scheme, cutting powder in holes in the substrate can be effectively removed, and inner hole plugging is prevented.