Drilling data has confirmed the presence of Mesozoic marine deposits in the northeastern part of the South China Sea. The Chaoshan depression is the largest residual depression in the northeastern part of South China Sea with an area of 3.7×104 km2. From Mesozoic to Cenozoic era, the Chaoshan depression experienced 6 stages of tectonic evolution: rifting during Late Triassic, depression during Jurassic, first tectonic inversion at the end of Late Jurassic, followed by subsidence during Early Cretaceous, second tectonic inversion at the end of Late Cretaceous, and regional thermal subsidence during Neocene. The depression was filled by shallow sea sediments, bathyal sediments, fluvial sediments and lacustrine sediments. The hydrocarbon source rocks of the Jurassic semi- enclosed gulf are thick with relatively high organic content, and strong hydrocarbon generation potential. Chaoshan depression has good oil and gas exploration prospects because of good oil and gas geological conditions.