The Egyptian Mediterranean Coast has five lakes; all of them, except Lake Maruit, are directly connected to the Sea. The objective of the present study in 2016 is assessing the environmental statement of Lake Maruit (water and sediment quality). The sample from 10 monitoring points distributed along the lake in addition to 3 samples from the main drains and for water samples (temperature, salinity, pH, BOD, DO, COD, eutrophication parameters (ammonia, TSM, nitrate, nitrite, reactive phosphate , silicate, TP and TN), heavy metals and microbiological parameters in addition to Total pesticides, PCBs and PHC) while for sediment samples (Sediment Types, Organic Carbon, Organic Matter Content, Water Content, TN, TP, heavy metals and Total pesticides, PCBs and PHC) were analyzed. The results revealed that water temperature of the Lake Basins showed variations and ranged from (12.8 - 31.5 °C) while the annual average concentration of Drains 22.5 ^oC, Salinity of the Lake ranged between (1.84 - 6.45 Ppt), while the annual average concentration of Drains 1.69 Ppt, the distribution pattern of seasonal variations of pH values was ranged between (7.24 - 9.04), while the annual average concentration of Drains 7.923, Distribution of DO showed a considerable wide range between(0.00 - 15.84 mg/l) , while the annual average concentration of Drains 4.54 mg/l, BOD in the Lake was ranged between (9.54 - 224.25 mg/l), while the annual average concentration of Drains 76.15 mg/l. Lake Maruit was considered a major source of pollution to the Mediterranean Sea through El-Mex Bay because it receives a huge amount of polluted water from three major sources. On the other hand, the lake water at present has no metal pollution problem. The main pollution problem is due to the oxygen-consuming wastes and the plant nutrients, which had led to depletion in DO.