Located in the tropical-subtropical region,the South China Sea is the largest marginal sea in the western Pasific Ocean. Due to the complexity of the hydrological,physical as well as chemical environment of the South China Sea ecosystem,significant variations exist in the abundance and productivity of the highly diverse phytoplankton community.So far,our understanding is still limited about the spatial and temporal distribution of phytoplankton and its regulating mechanism in this area.In this review,we gathered historical data,especially research results of the recent 20 years,summarizing and analyzing them in three perspectives, spatiotemporal distribution,environmental regulatory factor and the impact of global climate change.We emphasized the advances in the research methodology and important progresses in understanding phytoplankton ecology in the South China Sea.In addition,we proposed future research directions and highlighted areas where efforts should be invested to bring the South China Sea phytoplankton research up to speed with the equivalent ocean basins in the world.