Abstract: After the cessation of seafloor spreading in the Central Basin of the South China Sea, frequent magmatic activities have occurred. However, direct sampling and investigation of these active magmatic processes have been extremely challenging due to deep-water environment. We comprehensively analyzed the characteristics and episodes of post-spreading magmatic activities in the Central Basin of the South China Sea by interpreting 2D seismic profiles integrated with trawling sample data and relevant drilling research findings. A model of the relationship between magmatic activity and sedimentation was established, and seismic reflection features and seismic facies characteristics were interpreted. Results indicate that the magmatic activities in the Central Basin exhibit pulsating phases, forming numerous seamounts and magmatic diapirs characterized by multi-phase intermittent eruptions and shallow intrusions. Four major episodes of post-spreading magmatic activities were identified in the Central Basin. Three episodes at approximately 11.6 Ma, 7.5 Ma, and 5.3 Ma show remarkable consistency with radiometric dating of rock samples. Notably, the magmatic activity around 1.6 Ma was found to persist into recent times with extensive distribution. For the first time, evidence of magmatic activities during 2.6–1.6 Ma was discovered, challenging the previous notion of a magmatic quiescence period in this interval. Additionally, the study reveals that while some magmatic diapirs and submarine volcanoes formed through single eruptive events, others developed into larger-scale features through multiple volcanic activities.