Abstract: Restricted by large-scale and long-time series monitoring data acquisition difficulties, the impact of coastal urbanization on the overall spatial differentiation of chlorophyll-a concentration in coastal waters is insufficient.In this paper, the daily mean series of chlorophyll-a concentration in Shenzhen coastal waters in 2015 was analyzed by using singular spectrum analysis method to increase the richness of analyzable data, and then the relationship between coastal urbanization and spatial and temporal differentiation of chlorophyll-a concentration was studied.Results showed that land use types' area ratio, spatial distribution in buffers of each buoy point had a controlling effect on Chlorophyll-a Concentration in coastal waters, and the degree of influence of industrial land was stronger than residential land, which was stronger than agricultural land.The closer the buoy point is to the coastal zone, the longer the fixed fluctuation period of chlorophyll-a concentration and the greater monthly/weekly fluctuations.The increasing scale and distribution of industrial land and residential land will shorten the fluctuation period of chlorophyll-a concentration.