13 genera and 32 species of ostracodes were identified from lake sediment core HQ in the Heqing Basin, Yunnan Province. Five paleoenvironmental stages with a number of substages were divided in the basin since 150 kaBP based on the abundance, diversity and percentage of ostrocodes, in combination with pollen, total organic carbon (TOC), carbon/nitrogen ratio (C/N), and carbonate content. The general paleoclimatic conditions of the lake area are characterized by the alteration of cold-wet periods with warm-dry periods, with secondary fluctuations superimposed on the macroscopic trend, representing the regional paleoclimatic features. These paleoclimatic stages are generally correlated with the deep sea oxygen isotope stages of equatorial Pacific core V28-238 and those revealed by loess/paleosoil sequences of Mangshan section, in Zhengzhou, which shows the synchronism and differentiation of paleoclimatic changes. Due to the both effects of tectonic and paleoclimatic activities, the lake basin was completely captured by river at ca. 11790 aBP.