The invention discloses a method for detecting a broken pin of a drilling machine. The method comprises the steps of 1, designing the layout of inner holes of a plate to obtain the layout design drawing of the inner holes of the plate; 2, editing the layout design drawing of the inner holes of the plate by a script editor; adding a new hole at the side of the plate for the holes with the same type of aperture size on the original layout design drawing of the inner holes of the plate; enabling the drilling action of the new holes with different aperture sizes to be carried out after other holes with the corresponding aperture sizes are drilled, and taking the modified layout design drawing of the inner holes of the plate as a layout drawing provided with a broken pin detection module; 3, according to the layout drawing provided with the broken pin detection module, using the drilling machine to carry out the drilling work, obtaining a printed circuit board (PCB) subjected to the drilling work, and checking the new holes distributed at the side of the PCB to obtain the result of whether the broken pin exists in the drilling machine or not. The method is capable of reliably and efficiently detecting whether the broken pin exists in the drilling machine or not.