A solar power generation system includes a string, an inverter, a first shutoff device, and a second shutoff device. The string includes a plurality of solar cell modules connected in series. The first shutoff device turns OFF, in response to a first control signal from the inverter, a first switching unit and a second switching unit. The first switching unit is connected to an anode side terminal of the string and an anode side terminal of the inverter. The second switching unit is connected to a cathode side terminal of the string and a cathode side terminal of the inverter. The second shutoff device is configured to output a second state signal to the first shutoff device and cut off a solar cell module group and either another solar cell module or the inverter, in response to a second control signal from the first shutoff device.