The present study focuses on the Physico-chemical analysis of water samples collected seasonally from five sites longitudinally distributed along the Sebou River (North West Morocco). The objective of the study is to characterize and assess the degree of global pollution and to develop a Physico-chemical typology of the estuary. Sampling and analysis of Physico-chemical parameters were seasonal during the year 2019. The results show that the values of the Physico-chemical parameters vary according to the seasons, the distance of the site from the mother, and the discharge points of urban and industrial wastewater. Likewise, for various sites, the degree of pollution changes over the year and the qualitative and quantitative change in the discharge of wastewater discharged into the estuary. It should also be noted that the results showed that in all the prospected sites and for all the seasons, the waters of the estuary are severely polluted. For the typology of the waters of the estuary, the projection of the water readings in two factorial planes C1xC2 and C1xC3 showed the differentiation of several Physico-chemical groups according to the axes C1 and C2, and C3 with: C1 is a gradient of pollution of the estuary which results from both urban wastewater discharges and industrial wastewater. C2 is an axis representing an increasing gradient of mineral pollution and continentally about the sea. C3 axis represents a gradient of increasing pollution of multiple origins: agricultural, urban, and industrial.