The invention discloses a PCB manufacturing method for improving the alignment precision of an HDI plate through blind hole. The method comprises the following steps: S1: forming a blind hole by meansof laser ablation, and meanwhile, forming a positioning hole for assisting the mechanical drilling positioning by means of laser ablation; S2, when a through hole is mechanically drilled, assisting the positioning by the positioning hole formed by laser ablation. According to the PCB manufacturing method for improving the alignment precision of the HDI plate through blind hole, the positioning hole needed by the through hole processing is ablated while the laser blind hole is processed, when the through hole is drilled, the positioning hole ablated by the laser drilling is adopted instead ofthe pressed X-RAY targeted positioning hole, the through blind hole positioning system consistency is guaranteed, and the matching performance of the through blind hole in the manufacturing process ofthe outer-layer circuit is guaranteed.