Population growth and the modernization of industrial production have generated considerable water needs. This consumption has led to a disproportionate discharge of untreated wastewater, directly into receiving environments (Oceans, Seas, Rivers, Lakes, etc.). These discharges lead to the contamination of surface and groundwater and thus promote the spread of water-borne diseases. The main objective of this work is to describe the pollutant load of wastewater from the town of Mechrâa Belksiri (Kénitra-Morocco) and to classify them and identify their components and their intensity to seek an appropriate treatment allowing their subsequent reuse and reducing their harmfulness on their receiving environment Oued Sebou. The analysis of temperature, pH, redox potential, electrical conductivity, dissolved oxygen and salinity are recorded “in situ” using a multi parameter analyzer. The wastewater samples intended for physicochemical analysis in the laboratory were preserved according to the general guide for the conservation and handling of samples according to ISO 5667/3. Suspended Solids (TSS) are determined by filtration of a volume of waste water (100 ml) on a cellulose filter with a pore diameter of around 0.45 μm. The analysis of the BOD5 is determined by the breathing method using a BOD meter (OxiTop) and the COD, according to DIN 38409-H52 which is determined by oxidation by excess potassium dichromate at the temperature of 148°C, in an acidic medium and at boiling point. Wastewater from Mechraa Belksiri town has a pH of 7.2 (6.8 to 7.4) and an average temperature of 20.5°C (17.5 to 26°C) and an electrical conductivity of 3145 µs/cm. The average concentration of dissolved oxygen is very low at 0.35 mg/L and varies from 0 to 0.9 mg/L. Wastewater is loaded with organic matter estimated by Suspended Solid matter (average 446 mg/L and range 320 to 520 mg/L), BOD5 (280 mg O2/L) and COD (557 mg O2/L). The overall pollutant load of wastewater (BOD5/COD = 0.50; TSS/BOD5 = 1.59 and COD/BOD5 =0.98) presents satisfactory biodegradability and is well prepared for suitable biological treatment with activated sludge.