There has been a rapid development of photovoltaic (PV) power in recent years.Further analysis about the feature of PV power output was also a research focus.However, we have not got the mature PV power evaluation index system.After the data calculation, we found that the randomness of PV power output was less than that of wind power output.Therefore, we could choose alternatively some simple and refined index system to character PV power output.In this paper, we proposed an evaluation index system for PV power output.The index ‘PV power output season’ is used to describe the period of PV power output during different season.The index “averaged PV power output” is used to describe the level of PV power output.The index “maximum PV power output per day” is applied to quantitatively analyze the impact of PV power output on peaking service.The paper takes the output of an actual photovoltaic power station as an example, explains the indexes in detail and the application in curve classification.The results show that the proposed index system can directly describe PV power characteristics and form the typical curves, which has good application prospect.