Aiming at the current our country ecosystem key species to exist the problem that suffer to the serious threat. Key species concept, origins and the key species' important positions that sow in the e-cosystem inside are explained. At the same time, from many the angles of the theories and practice worth of key species and so on proceeded the analysis and how to protect effectively the ecosystem key species and proceeded the beneficial study are presented. It has a certain theories guides with realistic meaning to protect our country ecosystem.