A hydrogen circulation system for fuel cell includes a hydrogen supply pipeline, a return pipeline, a buffer tank, an ejector, a differential pressure valve, a solenoid valve, and a controller. The return pipeline connects a hydrogen outlet of a fuel cell stack and the hydrogen supply pipeline. The buffer tank is installed at the return pipeline. The ejector is installed at the hydrogen supply pipeline for connecting the buffer tank. The differential pressure valve is between a hydrogen source and the ejector for adjusting a pressure in the hydrogen supply pipeline based on a pressure difference between an anode inlet and a cathode inlet of the fuel cell stack. The solenoid valve is installed at the return pipeline between the buffer tank and the hydrogen outlet. According to an output voltage or a load of the fuel cell stack, a switch of the solenoid valve is controlled by the controller.