The invention discloses a light-driven SiC/GaN-based semiconductor device. The base electrode in the traditional BJT structure is cancelled, and ultraviolet light passes through a transparent electrode and a thin emitter region and enters a base region to introduce light excitation and generate electron-hole pairs in order to provide a base current for the base of the BJT. A rounded quadrangular frustum device structure is adopted, which improves the withstand voltage of the device. The invention further discloses a process for manufacturing the light-driven SiC/GaN-based semiconductor device.The device has the same advantages as the traditional BJT. Moreover, the light injection current gain, breakdown voltage, EMI immunity, switching speed and stability of the device are improved, the driving loss and the response time are reduced, and the manufacturing cost is reduced. The light-driven SiC/GaN-based semiconductor device and the manufacturing process are applicable to the field of low-power and high-power semiconductor power devices.