An intelligent diagnosis system for a power module. The system includes a power module, a hardware checking module and a diagnostic module. The power module has a temperature sensing element for obtaining a temperature difference between a starting minimum temperature and a current temperature. The hardware checking module has a current sensing element, a voltage sensing element and a magnetic coupling closed loop detection element for obtaining the current, the output voltage and the input voltage of the power module, and the hardware loop status, respectively. The diagnostic module calculates the number of cycles that have been operated, a measured impedance and an instantaneous power based on those measurement results, and calculating a risk index based on the number of cycles that have been operated, the temperature difference, the measured impedance, the instantaneous power and the hardware loop status, thereby determining the accumulation of the abnormality index record.