This application discloses a photovoltaic power generation system and method, and the system includes an inverter and at least one shutdown apparatus. A type of the shutdown apparatus includes at least one of a shutdown device and an optimizer; and an input end of each shutdown apparatus is connected to a corresponding PV module, and power of the corresponding PV module is output. In the system, when a parameter of the inverter meets a preset condition, some shutdown apparatuses are turned off to lower an input voltage of the inverter, and ensure that an input end of the inverter has a direct current source, and the system can operate as usual; and the preset condition is that the input voltage of the inverter is greater than a first preset voltage, or an input current of the inverter is less than a first preset current.