The invention discloses a method for regulating the threshold voltage of a complementary metal oxide semiconductor. The method mainly comprises that the implantation dosage and the energy of P-type ions are determined according the threshold value VTP of P-type metal oxide semiconductor, and P-type ion common implantation is conducted to a silicon wafer with gate oxide layer according to the result of the determination; and the implantation dosage and the energy of N-type ions are determined according to the threshold voltage VTN of N-type metal oxide semiconductor, the implantation dosage and the energy of the P-type ions, and photoetching and N-type ion implantation are conducted to the silicon wafer underwent the P-type ion common implantation according to the result of the determination and a P-well photoglyphy used to conduct P-well photoetching to the silicon wafer. By adopting the technical scheme, the VTP and the VTN can be accurately adjusted and the technological cost is saved.