Ivorian marine waters host a wide diversity of phytoplankton, which supports the development of various socio-economic activities. However, the proliferation of certain phytoplankton groups results in losses for aquaculture and fisheries, a decline in tourism activities, and negative impacts on human health. These phytoplankton groups also have significant consequences on the aquatic ecosystem. It is in this context that the present research was conducted, entitled: «Assessment of the toxicity of phytoplankton groups based on inherent optical properties (IOPs) of the ocean in Ivorian marine waters from 2010 to 2020» The data used include satellite imagery from SeaWiFS, MODIS, MERIS, and VIIRS sensors, providing information on chlorophyll-a concentration (aph), backscattering (bbp), absorption by colored dissolved organic matter (adg), as well as sea surface salinity and temperature. For data processing, SeaDAS v7.4 software was used to process and analyze concentration data. Ocean Data View software was then employed to extract concentration values for statistical analysis. The results include values for the ocean’s inherent optical properties (IOPs), salinity, and sea surface temperature. These values helped identify the major factors driving the proliferation of toxic phytoplankton and to determine the marine seasonal periods during which Ivorian coastal waters are more likely to be toxic. Based on the data obtained, concentration maps of aph, bbp, and adg were produced, and phytoplankton assessment curves (for Cyanobacteria and Diatoms) were analyzed in relation to IOPs. The findings revealed that marine seasons influence the proliferation characteristics of toxic phytoplankton in Ivorian waters, particularly during the main warm and main cold seasons.