This paper use d the hourly air temperature of 77 regional meteorological stations in Shanghai from 2011 to 2014 to study the temporal and spatial characteristics of the urban heat island (UHI) effect by the method of urban and rural comparison. Then, with the annual mean air temperature data of 20 national meteorological stations in the Yangtze River Delta region from 1961 to 2013, the influence of urbanization on the I_(UHI) in Shanghai was studied by the spatial filtering method. The main conclusions are as follows: The I_(UHI) showed a slowly increasing trend from 1961 to 2013 with a rate of 0.15~0.17℃ per 10 years and the maximum of annual I_(UHI) reached 1.10~1.33℃, which appeared in 2006. The acceleration of urbanization in Shanghai was conducive to the increase of I_(UHI)。Since the beginning of the 21st century, the increasing trend of I_(UHI) had slowed down, which was consistent with global warming breaks. In recent years, the urban areas of Shanghai were concentrated within the outer ring. The I_(UHI) of three different urban inner regions (the region within the inner ring, the region between the central and the inner ring, and the region between the outer and the central ring) showed the same diurnal variation characteristics. For the effect of different underlying surface, the I_(UHI) decreased gradually from the inner ring to the outer ring, which was obvious at night. Both the I_(UHI) and its diurnal variation were the strongest in winter, followed by autumn and spring, and the weakest in summer. The spatial distribution characteristics of I_(UHI) in spring and summer were similar (the temperature in the east of Shanghai was lower than in the west and a strong UHI center was concentrated in the northwest of Shanghai). The spatial distribution characteristics of I_(UHI) in autumn and winter were similar (the temperature in the west of Shanghai was lower than in the east and the strong UHI center was located near the urban area). It could be related to the monsoon.