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Based on the data of sunshine duration， cloud amount， surface vapor pressure， and precipitation of 11 meteorological stations in Shanghai， the temporal and spatial variation characteristics of sunshine duration and the influencing factors from 1960 to 2009 are analyzed using the linear trend， MannKendall test and other methods. The results indicate that annual sunshine duration in Shanghai reduced significantly in recent 50 years. In summer， autumn and winter， sunshine duration reduced significantly， but in spring， it changed insignificantly. The sunshine duration had an abrupt change in 1980. From 1983， the sunshine duration reduced significantly in Shanghai. Spatially， the sunshine duration reduced in the whole area in recent 50 years， more obvious in the northern parts than in the southern parts of Shanghai. There was significant negative correlation between annual sunshine duration and annual precipitation as well as annual precipitation days， so the increase of annual precipitation amount might contribute to the reduction of annual sunshine duration. There was basically significant negative correlation between seasonal sunshine duration and seasonal cloud amount， surface vapor pressure， and precipitation in four seasons. The increase of summer precipitation amount might contribute to the reduction of summer sunshine duration， and the increase of winter precipitation amount and surface vapor pressure might contribute to the reduction of winter sunshine duration.