A characterization of the geothermal regime of sedimentary basins and associated subsurface formation temperature is crucial for the assessment of hydrocarbon generation, preservation, and estimation of regional geothermal energy potential. The Upper Yangtze area of the South China is one of the longlasting regions for marine oil and gas exploration. Recently, it is the emerging area for shale gas exploration in China. The accurate characterization of the thermal regime in this area could constrain potential assessment of shale gas. However, further investigation is needed given the poor data coverage and associated inconsistency of previous studies. In this study we have combined the measured rock thermal properties and newly acquired steadystate temperature logging data with drill stem test temperature data to determine the presentday geothermal gradient and heat flow pattern, and estimate the subsurface formation temperaturesatdepth in the range of 1000~6000 m in the upper Yangtze area, along with temperatures at the bottom surfaces of two major Paleozoic marine source rocks in the Sichuan Basin. Our results demonstrate that this area has a moderatelow geothermal regime, and its presentday geothermal gradient and heat flow range (mean value) are 10~74℃/km (24℃/km) and 27~118mW/m2 (64mW/m2) respectively. Regional heat flow and temperature increase from the northeast to the southwest, showing a trend of "low in the northeast and high in the southwest". In the northeast, the west of Hubei and the north of Hunan province are characterized by low temperature areas; in the middle, the majority of the Sichuan Basin shows a moderate temperature; in the southwest, the Yunnan Province shows high temperature. This spatial variability of geothermal pattern in this area is mainly controlled by differential tectonics and magma activities. On the basis of predicted reservoir temperature and other geological and geochemical conditions, we propose that the shale system of the Lower Silurian Longmaxi Formation in ShizhuFuling, Weiyuan-Zigong-Luzhou and Yibin- Changning are likely to be the most favourable areas for shale gas exploration in this region.