So far the processes of vegetation evolution in the northern margin of East Asian summer monsoon have been still poorly investigated on the glacial-interglacial time scales. In this plan, a 36.55 m-long sediment core (U11) recovered at Ulagai Lake in eastern Inner Mongolia will be analyzed for pollen assemblage, based on the age model constructed with AMS 14C and OSL dating results, to reveal the process of vegetational evolution in the lake region during the last two interglacial-glacial cycles, and to quantitatively reconstruct the history of changes in the precipitation and temperature using a set of pollen-climate transfer functions intended for temperate eastern Asia. It is expected to reveal the patterns and mechanisms of the climatic and environmental change over the lake region on both orbital and millennial time scales. Owing to the location of Ulagai Lake within the ecological sensitive zone and the continuity and high resolution of the U11 core sediments, studies of vegetation evolution and climate change over the lake region during the past 210 kyr would improve our understanding of the past changes, characterized by cyclical variation on the orbital scale and by abrupt change on the sub-orbital scale, in the vegetational pattern and precipitation variability in the semi-arid region of northern China, and contribute to a precise prediction of the future climatic and environmental processes.