On the basis of data from Shanghai Central Observatory (Longhua) and its nearby rural stations for more than 20 years,we discuss the important features of sunshine in Shanghai urban area and the choice of house orientation. 1.The diurnal and seasonal variation in sunshine in Shanghai urban area is dominant.It is caused by the latitude situation,meteorological conditions and urban artificial factors. 2.By comparing the simultaneously obtained observed data from Longhua and its nearby rural stations (Baoshan,Jiading,Chuansha and Shanghai counties),it is found that in the urban area both sunshine hours and percentage of possible sunshine are less than in rural areas. This is due to much more artificial heat,pollutants and condensation nuclei to the urban atmosphere.The obvious effect on urban climate is much more low cloudiness and overcast days but less fine days and sunshine. 3.In order to obtain good sunshine (more sunshine in winter and less sunshine in summer) and good ventilation in summer,the favorable orientation of a house in Sbanghai urban district is toward SSE.This orientation can also save the building area and energy consumption.