Based on seismic sections, drilling data and logging profiles, the spatial-temporal evolution of the deltas that developing in southern Nansha area during Tertiary sedimentation is reconstructed and the dominating factors controlling development of each delta are discussed. It is indicated that the deltas migrated from the west side of the west Baram fault to the east side of the west Baram fault along the coastline (NE-SW) while they advanced with progradation from the land to the sea in the longitudal direction(NW-SE) during Oligocene and Pliocene. Such an evolution process is controlled by eustacy and the migration of orogenic belts which is caused from the scissors-typed subduction of the ancient South China Sea. Source rock, reservoirs and traps can be divided into different stages and zones. By synthetic analysis, three zones of hydrocarbon accumulation relative with the evolution of the deltas are divided: the Balingian delta oil-rich zone in Zengmu Basin, the Baram delta oil-rich zone and the Meligan-Champion delta oil-rich zone in Brunei-Sabah Basin.