Abstract: The Zhujiangkou Basin is a large Cenozoic oil-and gas-bearing basin on the continental shelf off Canton, China. The first test hole was spudded October, 1977, and industrial oil flow was obtained from Pearl No.5 Well Aug., 1979. It occupies an area of approximately 150,000 square kilometers. As the tectonic movement of Late Eocene brought the land area widely uplifted and the sea area rapidly subsided, the basin has turned out to be a marginal depression, owing to the faulting tension of earth crust. It has undergone three stages of development. Eight second-order structural units can be recognized within the basin, including three major depressions. The Cenozoic stratum exceeds 6,000 meters in thickness, containing rich organic material, excellent source and reservoir rocks, and various types of local structural traps. The regional oil-and gas-bearing sequences of the basin with oil of high quality and abundant reserves are well developed. The Zhujiangkou Basin is one of the few major oil-and gas-bearing basins which have not been explored and developed in the world so far. Its significance has already been realized by the petroleum geological community both domestic and abroad.