The invention relates to a circuit board drilling tool for processing a PCB (Printed Circuit Board). The circuit board drilling tool comprises a drill body, wherein three spiraling chip grooves are formed in the drill body, the long chip groove spirally extends to the tail end of the drill body from the position of a drill point, the short chip groove is formed in the front section of the drill body, the short chip groove and the long chip groove are not parallel due to different spiral angles and are intersected ultimately, the back chip groove is formed at the back after the long chip grooveand the short chip groove are intersected, finally, the short chip groove and the back chip groove are intersected with the long chip groove from a separate state, and a single main cutting edge is formed on the drill point. The widths and the spiral angles of the chip grooves are different, so that the purposes of assisting the drill to stably cut and quickly discharging chips are achieved, thedrilling quality is increased, the hollow wall roughness is guaranteed, the circuit board drilling tool has the advantages of good rigidity, high drilling accuracy and difficulty in breaking needles,and the hollow wall roughness can satisfy the requirement.