Abstract: By TCAD, the model for single event transient(SET) in SOI 4H-SiC FinFET device at 14 nm technology node was simulated. With the temperature range from 258 to 398 K, the influence of the bias voltages on SET was analyzed and the potential mechanism was also discussed. The simulation results indicate that due to the temperature increase, the Femi energy of the device changes and the band gap reduces, which increases the driven current. Then it leads to improve the immunity to SET. However, because of the bias voltage increase, the inner electrical field in the device enhances, resulting in the rate of the charge collected increase, which increases the sensitivity to SET. Due to the competitive relationship between the impacts of the temperature and the bias voltage on SET, when the temperature is 398 K and the bias voltage is 0.4 V, the weakest SET is obtained. Compared with SET obtained at 300 K and 0.8 V, the weakest one is with the relative decrements of the current peak and the collected charge being 22.77%, 50.83%, respectively.