Abstract: With the rapid development of photovoltaic power generation in China, the proportion of photovoltaic power generation in large-scale power grids is increasing. The integration of photovoltaic power generation into the power system can effectively alleviate the deterioration of the current ecological environment, accelerate the development and utilization of renewable resources, and also provide a strong driving force for the transformation of China's green energy structure. However, the photovoltaic power generation system is easily affected by the external environment such as light intensity, weather type, atmospheric temperature and humidity, resulting in instability and intermittenity of power generation output, which has a certain degree of impact on the power grid, so the power prediction of photovoltaic power generation system has become the main research direction of the power sector and related fields. This paper introduces the photovoltaic power generation system and the influence factors of photovoltaic power generation system output, analyzes the current domestic photovoltaic power generation system output power prediction methods by referring to relevant literature, and puts forward some existing problems and solutions in the current research.