With the increasing power demand of SAR satellite loads, the requirements for the power system have become more stringent. In the power system of SAR satellites, the use of SiC MOSFETs instead of Si MOSFETs as the switching devices of the power conversion circuit can effectively improve the conversion efficiency and power density. Therefore, the study of SiC MOSFET driver circuit is of great significance for optimizing the power system of SAR satellites. In this paper, a gate driver circuit suitable for the power system of SAR satellites is designed based on the characteristics of SiC MOSFET with isolation and high-speed switching characteristics, and each module in the circuit is analyzed in detail. In addition, this paper constructed a buck/boost circuit and studied the effect of the circuit efficiency under different circumstances by adjusting the output power in the circuit. The experimental results show that the driver circuit is capable of realizing the fast switching of SiC MOSFET with low switching loss, which is suitable for the high-frequency circuits applied in the SAR satellite power system. Meanwhile, the oscillation suppression circuit in the circuit also improves the stability of the SiC MOSFET driver.