There are little affects by human activities in Lugu Lake area, and it’s sensitive to the climatic changes. Therefore, Lugu Lake is an ideal place to carry out the paleoclimate study. In this study, we drilled a 103 cm long core in Caohai, Lugu Lake area. In total of 52 samples were obtained for pollen analysis with the interval of 2 cm. The dating was measured by AMS-14C method, and the calibrated age of the bottom is 3455 cal. yr BP. Abundant of pollen and spores were obtained from all the samples. The vegetation was described as follows: Pinus trees are predominant through all this period, and Tsuga trees are also with frequent appearance. Quercus trees dominate the angiosperms, Castanea and Oleaceae both occur frequently. Gramineae is the main component of herbs, together with Polygonaceae, Asteraceae and Cyperaceae. Ferns are one important composition of the understory vegetation, which including Osmunda, Lycopodium and Hymenophyllaceae etc. In addition, Caohai is a seasonal wetland. Therefore, aquatic plants are common to see, which are mainly composed by Typha, Zygnema and Spirogyra. In order to obtain the climatic changing curves since late Holocene in Lugu Lake area, we applied Coexistence Approach to the four pollen zones. The MAT (the mean annual temperature) and MAP (the mean annual precipitation) are listed as follows: 3455 cal. yr BP to 2585 cal. yr BP, MAT = 11.5-18.6 ℃, MAP = 797.5-1484.3 mm; 2585 cal. yr BP to 1699 cal. yr BP, MAT = 11.7-18.6 ℃, MAP = 617.9-1523.1 mm; 1699 cal. yr BP to 595 cal. yr BP, MAT = 8.5-18.6 ℃, MAP = 797.5-1484.3 mm; 595 cal. yr BP to present, MAT = 5.7-18.6 ℃, MAP = 617.9-1484.3 mm. The climate since 3455 cal. yr BP went through four phases: getting warmer slightly, being colder, still tend to colder and getting warmer again. We also compared our climatic changing curve with other records (such as δ18O curves of Greenland ice core and Dunde ice core) which shows similar changing trend. The Medieval Warm Period, Little Ice Age and Current Warm Period are all can be observed.