The present invention provides a modeling method of a SPICE model series of a Silicon On Insulator (SOI) Field Effect Transistor (FET), where auxiliary devices are designed and fabricated, electrical property data is measured, intermediate data is obtained, model parameters are extracted based on the intermediate data, a SPICE model of an SOI FET of a floating structure is established, model parameters are extracted by using the intermediate data and data of the auxiliary devices, a macro model is complied, and a SPICE model of an SOI FET of a body leading-out structure is established. The modeling method provided in the present invention takes an influence of a parasitic transistor of a leading-out part in a body leading-out structure into consideration, and model series established by using the method can more accurately reflect actual operating conditions and electrical properties of the SOI FET of a body leading-out structure and the SOI FET of a floating structure, thereby improving fitting effects of the models.