Abstract According to the abnormal curve of opening characteristics in the process of double pulse test, the failure of 6.5kV/100A SiC module is judged, and it is preliminarily concluded that the gate of the module is damaged; The failure of the module is located by means of module anatomy, static characteristics test and chip screening test. It is concluded that the failure of the module is caused by the abnormality of two SiC MOSFET chips in the module; The damage of the chip was located by using stereomicroscope, OBIRCH, SEM and other equipment, and the root cause of MOSFET failure was studied by stripping anatomy. The preparation process of the gate and passivation strip on the MOSFET was poor, and the introduction of defects led to the breakdown of the gate unable to withstand high voltage.