Manufacturing method of semiconductor device

A manufacturing method of a semiconductor device is provided which can improve the performance of the semiconductor device. Ion implantation is applied to nMIS regions 1A and 1B and pMIS regions 1C and 1D of a semiconductor substrate 1 with offset spacers formed over sidewalls of gate electrodes GE1, GE2, GE3, and GE4 to thereby form extension regions for source and drain. In this case, a different photoresist pattern is used for each of the nMIS regions 1A and 1B and the pMIS regions 1C and 1D to individually perform the corresponding ion implantation. Every time the photoresist pattern is re-created, the offset spacer is also re-created.