Based on multi-proxy investigations such as grain size, content of carbonate and loss on ignition of the deep core of the ancient lake in the Heqing basin, the northwest of Yungui Plateau, it is reconstructed for a 2. 78 Ma paleoenvironmental evolution. The result of magnetic stratum indicates that the Heqing lake basin was formed at about 2.78 Ma. Further, the multi-proxy analysis reveals that there had been three major environmental stages in the Heqing basin since 2.78 Ma, namely the lake basin accumulated water to be a lake in 2.65 Ma,and the height difference between the mountains and basin increased twice at about 1.55 Ma and 0.99 Ma. These stages couples well with Qingzang movement phase B，phase C and Kunlun-Huanghe movement respectively.