The tectonic movement taking place at the end of Cretaceous and the beginning of Cenozoic had opened the Cenozoic phase of polycyclic tectonic movements,then the whole crust of the South China Sea had been mainly subjected to the regional stress field of tectonic tension,which was characterized by rifting depression.Seven times of regional tectonic movement and sedimentation had been assembled into a geological development history of polycyclic oscillation.Especially,the tectonic movements were strongly intensified at the end of Cretacious and the beginning of Paleagene,between Late Eocene and Mid-Oligocene,during Mid-and Late Miocene.These three times of tectonic movement had built the most important regional tectonic interfaces in the South China Sea.Crust movements of the South China Sea were the result and epitome of interaction of the Eurasia,Pacific and Indo-Australia plates,that is,they were introduced by polycyclic changes of directions,rates and strengths of lithospheric movements and asthenospheric flows across the Pacific and Indo-Australia plates. The tectonic movement taking place at the end of Cretaceous and the beginning of Cenozoic had opened the Cenozoic phase of polycyclic tectonic movements, then the whole crust of the South China Sea had been primarily subjected to the regional stress field of tectonic tension, which was characterized by rifting depression. Seventh times of regional tectonic movement and sedimentation had been assembled into a geological development history of polycyclic oscillation. Especially, the tectonic movements were strongly intensified at the end of Cretacious and the beginning of Paleagene, between Late Eocene and Mid-Oligocene , during Mid-and Late Miocene. These three times of tectonic movement had built the most important regional tectonic interfaces in the South China Sea. Crust movements of the South China Sea were the result and epitome of interaction of the Eurasia, Pacific and Indo- Australia plates, that is, they were introduced by polycyclic changes of directions, rates and strengths of lithospheric movem ents and asthenospheric flows across the Pacific and Indo-Australia plates.