The invention provides a drilling positioning method for a PCB (printed circuit board). The method comprises the following steps: S1) marking a reference line (9) on the PCB, wherein an effective region on the PCB is divided into two through the reference line; S2) forming a main positioning hole in a corresponding position at each of the two ends of the reference line in an edge region, and forming an auxiliary positioning hole in each of the other edge regions corresponding to the two effective regions; and S3) positioning the PCB on a drilling machine through the two main positioning holes and any one auxiliary positioning hole, drilling the effective region corresponding to the edge region with the auxiliary positioning hole, positioning the PCB on the drilling machine through the two main positioning holes and the other auxiliary positioning hole, and drilling the other effective region. According to the method, the drilling position accuracy of the PCB can be effectively improved, so that the product quality of the PCB is improved.