AbstractThe Three Gorges Project ( TGP) ,now under const ruction , will cause hydrological variation of Yangtze River. Reservoir inundation and large amounts of resettlement of people are direct and key factors affecting biodiversity conservation of the affected area. Based on the latest field investigations and research findings , this paper reviews the related issues on biodiversity conservation of TGP. For the Three Gorges reservoir area , there are 144 vegetation types , 6388 high plant species , 3418 insect species , and 500 terrest rial vertebrate species. The reservoir inundation and resettlement are major factors affecting terrest rial life , in which 36 vegetation types will be affected and four endemic plant species will be submerged (one species range fully submerged and three species partly) . There are 350 fish species and 1085 aquatic species including plankton , benthic and aquatic plants in Yangtze River which are mainly affected by the hydrological variation. Some endemic or endangered aquatic lives ,such as Chinese River Dolphin , Chinese Finless Porpoise , Chinese sturgeon , Chinese Paddlefish , Dabry Sturgeon , Chinese Sucker and four fish species (Black Carp , Grass Carp , Silver Carp and Bighead) , are worth paying more attention to. The populations of these species have already sharply de creased due to non-Three Gorges Project factors. With the const ruction of TGP , many countermeasures will be taken , such as setting up a long-term ecological and environmental monitoring network , setting up nature reserves for conservation priorities , and implementing artificial breeding and stocking for the endangered fishes , to reduce negative impacts on biodiversity and thereby to assure no loss of species from the TGP.