Abstract: A method for testing the total dose effect of a SiC MOSFET device, realizing verification of the complex total dose effect of the SiC MOSFET. The test steps sequentially comprise: testing a tested device before irradiation; performing annealing treatment on the tested device before irradiation; performing an irradiation test on the tested device; performing annealing treatment on the tested device after irradiation; performing test data analysis and processing on the tested device after irradiation. In the test process, threshold voltage shift caused by total dose radiation-induced defects and threshold voltage shift caused by near interface trap charges inherent near a SiC MOSFET interface are measured respectively, comprehensive analysis and calculation are carried out on the test result, the total dose effect resistance capability of the SiC MOSFET device can be given, and a certain guiding effect on device reinforcement is achieved.