Today we are facing a series of climatic problems such as elevation of P_(CO_2),global warming,and ocean acidification, which may lead to the sixth mass extinction.The similar extreme climate has been happened repeatedly in the Earth history. Therefore,taking history as mirror will help us to better understand the nature of these problems and resolve them.The most severe extinction happened during the Permian-Triassic transition(252Ma),eliminating over 90%species.In the past few decades, the process and cause about this extinction event have become the key scientific questions that need to be uncovered.Recent studies show the extreme climatic events we are facing now have been occurred near the Permian-Triassic boundary.The main purpose of this paper is to summarize recent studies on biotic and environmental events during the Permian-Triassic transition, including extinction process,pattern,and causes of the extinction,and survival mechanisms in its aftermath.