The growth and lateral linkage of the normal faults are the most basic 3D geological structural problems. Deeply analysis of 3D temporal and spatial evolution processes of the normal faults is very important for the formation and evolution of normal fault system in sedimentary basin. The spreading time and affected regions of the South China Sea are the focus issues in the geological field. Lufeng sag, located in the Pearl River mouth basin in the northern South China Sea, has developed a large number of normal faults and covered with high ~ resolution 2D seismic profiles and drilling data, which has become one of the ideal areas to study the above problems. Through characterizing the 3D seismic interpretation and modeling of the Lufeng sag, this study aims to provide a detailed case of 3D temporal and spatial evolution processes of the normal fault system. The results reveal that the growth and linkage processes of the main fault F1 can be described as three periods: ① During Late Cretaceous to Early Paleocene, two isolated faults formed and grew, respectively; ② Those fault segments merged laterally into F1 fault, and the relay ramp developed at the connection place between Early Paleocene and Early Oligocene; ③ The F1 fault continues to grow laterally on both sides from Late Oligocene to the Middle Miocene. Moreover, the expansion index and fault displacement are used to analyze the activity intensity of the fault F1, and we find that the fault slip of the F1 increases first and then decreases abruptly, and its shifting time occurred at the T60 reflector, ~23 Ma, which better corresponds to the spreading termination of the northwest subbasin, and highlighting that the spreading of the South China Sea has affected the Lufeng sag. Combined with previous studies on the Pearl River mouth basin, we preliminarily think that the spreading of the South China Sea has passed through the Lufeng sag, and its northernmost boundary may be corresponding to the Littoral fault zone, which located at the southern margin of the South China continent. Thus, our study enhanced our understanding of the 3D temporal and spatial evolution processes of normal fault system, and provide additional constraints for studies of the spreading processes of the South China Sea.