The invention discloses a transistor small signal equivalent circuit model, which comprises an electrode parasitic part at each electrode part, wherein each electrode parasitic part comprises a step inductive resistance structure; each step inductive resistance structure comprises a parasitic inductor and a parasitic resistor which are mutually connected in series; the high-order parasitic resistor is mutually connected with the high-order parasitic inductor in series, and then is connected with the parasitic resistor in parallel. The module better reflects the high-order parasitic effect relating to semiconductor active devices at high frequency, therefore, the performance of a transistor can be simulated more accurately, and the transistor small signal equivalent circuit model can be used for circuit design, or guiding device preparation and process improvement.