Abstract: The sedimentary sequences since 13 ka BP have been established in the Bah lake area, Kahu Co, northern Tibet, through a study of a lacustrine section. The climate since 13 ka BP may be di;cided into two dry-cold phases and two moist phases, of which the two moist phases and the dry-cold phase of the second cycle may he broadly correlated with the first and second new Hypsithennal phases and second new glacial phase in the northern hemisphere. This in the main reflects the general regularity of global climatic change since the last deglaciation. The response of the interior of the Qinghai-Tibet Plateau to the global climatic change is relatively sensitive.