A lot of things have been prepared for the Three Gorges Project for thirty years, but some questions still need to be studied. The problems from environment is an obvious one. The developed countries in the world have practised the evaluating systems to the effect impacting environment, and put the ecological problems at the first place. To protect the environment, a few countries have stopped constructing the large-scale dams. Many bitter lessons, such as the late troubles of the Three-Gates-Gorge Dam of our country, the disasters producedby the collapsing of both Banqiao and Shijintan Reservoirs, and the pitiful pictures of near 5,000 dams bursted in cur country during thirty years, have created astonishing losses. The sequelae left from the drowning of the reservoirs and the emigrants' live have came into an incovenient social problem difficult to solve. Past lessons, if not forgotten, is the guide for the future. The internal and external lessons ought to be drawed, the scientific research and the evaluate to all the effects listed above on the ecological environment be strengthened in practice in order to take preventive measures when the Three Gorges Project is constructed. Then, it is possible to bring benefit to mankind.