Abstract: Based on the observed data of 134 meteorological stations and ERA-interim reanalysis data in Sichuan Province (SCP), the spatial-temporal characteristics of persistent high temperature event and its corresponding atmospheric circulation are analyzed. The results showed that an unprecedented persistent high temperature event occurred in SCP from August 11 to 26, 2016, which accompanied with the highest temperature values and the longest duration since 1968. The critical circulation system was the westward-expanding and intensified western Pacific subtropical high. Correspondingly, the intensive South Asia high moved eastward significantly, directly accelerated the movement of the western Pacific subtropical high. Due to the abnormal anticyclone in SCP, downdraft was beneficial to the formation of high temperature. In addition, the synergistic effects of higher geopotential height of East Asia and northerly subtropical westerly airflows blocked cold front southward. Anomalous divergence of water vapor flux in the lower troposphere is coupled with the strong downward motion, which results in less rain and prolonged high temperature. It revealed the characteristics and circulation mechanisms on the typical high temperature episode in SCP.