Global warming has a significant effect on global and regional hydrological cycles and is expected to exacerbate the uneven distribution of rainfall in various regions, thereby influencing water-related human activities (e.g., agriculture) and the development of human society, especially in densely populated East Asia. As an analog to predict the future impact of global warming on hydrological regimes, the Paleocene-Eocene Thermal Maximum (PETM) at ~56 Ma is the most prominent and extensively studied Paleogene hyperthermal event, and it featured rapid and extreme global warming that caused intense environmental effects. However, the contradictory effects/mode of precipitation during the PETM has constrained our understanding of the hydrological response to global warming. Moreover, compared with marine records, continental sedimentary records of the PETM are very limited, and most are typically limited to weathered, often discontinuous, outcrop exposures, and relevant records of environmental perturbations in Asia are lacking. This study presents the first detailed record of the PETM in the Jianghan Basin, central China, and identifies the environmental and hydrological changes across the PETM. Based on high-resolution carbon and oxygen isotopes in the lacustrine carbonates (mainly calcite and dolomite) in the deep drill core SKD1, we identified the PETM event at the boundary of the Shashi and Xingouzui Formations. The carbon isotopic values of carbonate ( δ 13 C carb ) and calcite ( δ 13 C calcite ) show large negative excursions (~10.7‰ and 8.7‰, respectively) during the PETM. The oxygen isotopic values of carbonate ( δ 18 O carb ) and calcite ( δ 18 O calcite ) also show large negative excursions (7.9‰ and 6.1‰, respectively), indicating increased precipitation and a wetter climate across the PETM, as evidenced by the disappearance of evaporites and the dominance of calcite in the carbonates. Increased precipitation with elevated pCO 2 concentration might have caused the anomalous large negative excursion of the δ 13 C carb values in the SKD1 core and provided favorable living conditions for the oldest known primate, whose fossil was found in the Jianghan Basin. The δ 18 O carb and δ 18 O calcite values increase and show high-frequency and large-amplitude fluctuations above the PETM interval, indicating rapid shifts between wet and dry climatic conditions in an overall arid climate after the PETM. • The first detailed PETM record in the Jianghan Basin was found in deep drill core SKD1. • The carbonate carbon isotopes show large negative excursions (CIE, ~ − 10.7‰) during the PETM. • Precipitation in the Jianghan basin increased across the PETM. • Increased precipitation might have caused the anomalous large negative CIE in the carbonate.