Abstract: The Three-Gorge Engineering Project which attracts worldwide attension now enters a clucial construction stage. In this paper the long-term engineering geological exploration and reasearch of the Three-Gorge project area are described from the regional stability and seismic risk, engineering geology of the reservoir area and environmental geology, reservoir-induced earthquake, engineering geology of dam site and biuldings, and natural construction materials, and an emphasis is made on the geological and seismological problems of the Three-Gorge engineering project. Finally, an experiential summarizing is made on the geological exploration of the huge engineering project.