Abstract: The Yiyang area during the late Permian-early Triassic Boundary (PTB) was located in the southern margin of the North
China Craton in the lower latitudes of eastern Tethys. A set of continental clastic lithofacies was developed in this area and is ideal for
studying the paleoenvironment and paleoclimatic changes of the late Permain-early Triassic. This paper is based on previous research
and field observations to study the sedimentary characteristics in Yiyang area by investigating the lithology, sedimentology and
paleobiology. A lacustrine-fluvial sedimentary environment is identified and the paleogeography of Yiyang area is reconstructed. The
overall climate conditions during this period were hot-semiarid and extreme drought occurred at the end of the Changsingian and the
early Olenekian. The periodic (seasonal) climate could be controlled by Pangean Megamonsoon. The evolution of paleoclimate and
paleoenvironment may have played an important role in the end-Permian massive extinction and inhibited Triassic biotic recovery.

Key words: Late Permian-early Triassic, paleoenvironment, paleoclimate, lacustrine-fluvial deposits