Abstract: In order to study the change trend of cloud cover and its relationship with meteorological factors in the area of southern Qinghai Lake, based on the data of cloud amount from 1961 to 2014 of Gonghe Weather Stations in the area of southern Qinghai Lake, the authors analyzed the change trends of total and low cloud cover and its relationship with climatic factors. The results showed that the average total cloud cover had a slow increasing trend since 1961, but the average low cloud cover significantly increased. Mutation analysis showed that the spring total cloud cover had a mutation in 1963, and the spring low cloud cover had a mutation in 2003, the winter low cloud cover had a mutation in 1999, and the annual, summer and autumn low cloud cover had a mutation in 2002. The greatest impact on total cloud amount is the evaporation, followed by relative humidity and precipitation. The total cloud cover was significantly and negatively correlated with the average wind speed, the low cloud cover had a significantly positive correlation with the average temperature.