The largest mass extinction event in geological history, probably related to the extreme paleoclimate changes, occurred at the Permian- Triassic boundary. Previous studies on the paleoclimate have mainly focussed on the continuous marine strata with limited systematic studies on terrestrial strata. In this paper, we focus on the Upper Permian Sunjiagou Formation in the Yiyang area of western Henan with the aim of reconstructing paleoclimate by using sedimentology, mineralogy and elemental geochemistry. Based on the comparison with other terrestrial strata, the impact of climate change on the Permian- Triassic extinction are discussed. The results show that: ① the Sunjiagou Formation has experienced the evolution process of shore lacustrine- shallow lacustrine- shore lacustrine subfacies in the Yiyang area. The lithofacies changes, absence of fossils, a great number ofcalcareous concretions and other sedimentary structures show that the climate of the upper member is hotter and more arid than that of the lower member.② The geochemical elements and clay mineral assemblages also indicate that the climate experienced a transition from warm and humid to hot, arid and semi- arid.③ The conclusion of this study is basically consistent with other terrestrial strata in the same period, reflecting the consistency with global paleoclimate transformation. The factors such as abrupt rise in temperature, extreme drought and destruction of the terrestrial ecosystem at the end of the Permian may have been the main reasons that led to,or accelerated,the extinction of terrestrial life. This study has guiding significance for the relationship between climate change and biological extinction at the Permian- Triassic boundary and provides new evidence to explore the causes of global biological extinction in this period.