Abstract: Closed lake in arid region is sensitive to the climatic change．Through the analyses of environmental proxies from the sediments in Aibi Lake—a closed one in the arid region．the characteristics of climatic environment in early Holocene epoch were studied．The pollen assemblage and other geochemical indices show that．the temperature was somewhat low in the period of 8.0 to 11.5 cal ka BP as a whole，but in its earlier stage(11.5 to 10.6 cal ka BP)the temperature was higher，acompanied by more precipitation． In the transitional stage from early Holocene epoch to middle Holocene epoch(8.9 to 8.0 cal ka BP)the climate fluctuated remarkably．Especially，the three layers of peat sediments revealed a strong instability of climate in early Holocene epoch in Aibi region．All informations on the development of peat and the experimental data of pollen and stable isotopes imply that the climatic condition at 8.2 cal ka BP．8.6 cal ka BP and 10.5 cal ka BP was noticeably cold and humid, and could be regarded as three cold and humid events in early Holocene epoch．