A perfect and unique archaeological site is recovered at the Zhongba of the Three Gorges where the legacy of human culture and activities, and the information of environmental changes is recorded completely in a litho stratigraphical sequences since the Late Glacial stage. This is also the best place found to study the environmental changes. Rb and Sr contents in the litho stratigraphical sequences have been tested and the results show a high value of Rb content and low value of Sr content, with a variable Rb/Sr ratio through the profile. The value of Rb/Sr ratio illustrates the natural environmental changes. According to the characteristics of distribution of Rb, Sr and Rb/Sr ratio in the litho stratigraphical sequences at the Site, four distinct periods can be divided(1) Late Neolithic Age(5.1～ 4.3kaB.P.);(2) Late Shaang Dynasty and Xizhou Period (3.4～2.8kaB.P.); (3) The Late Zhan guo Early Qinhan Dynasties(2.4～2.1kaB.P.);and (4) Yuan and Ming Dynasties (0.8～0.7kaB.P.). The high value of Rb/Sr Ratio show that climatic changes were rapid and cold and humid climatic conditions were overwhelming during and after the Neolithic Age. No evidence shows any warm period in the Three Gorges since the Mid Holocene Period. The climatic characteristic in the area is probably related to southeast and southwest monsoon and regional topographic relief. Two warm periods were found separately in Sui Tang Dynasties (1.5～1.1kaB.P.) based on the evidence of Rb/Sr Ratio. Human activities, such as producing salt, were affected by the climatic changes, which might be closely related to the climatic changes in the region of the Three Gorges.