Abstract: Based on 99 clear sky Terra satellite images of Chengdu City in 2005-2010, and by using a novel automatic extraction method of suburb temperature, i.e., each citycircle temperature jump, this paper studied the spatiotemporal variation characteristics of the urban heat island (UHI) effect in the City in 2005-2010, and analyzed the causes of the variation characteristics. In the study period, the central area of the largest and strongest UHI was in the Jinhua Town located in the southwest of Chengdu. The UHI effect had no significant spatial variation, but the range and intensity of the UHI effect tented to be decreased. The intra-annual UHI intensity and area within the ring roads showed a threepeak distribution pattern, with the peak values appeared in April, July, and October, and the intensity reached the maximum in July. The UHI intensity in Chengdu was attenuated by the decrease of air temperature and the increase of precipitation and urban vegetation cover.