The Mariout Lake is considered an important natural resource for fish production in Alexandria Governorate, it has been subjected to various types of pollution, the lake acts as a receptor for domestic wastewater and industrial wastes. So this study was conducted to determine the effect of environmental impacts and pollution on chemical properties of different cores of Mariout lake sediment, Surficial (0-10cm) and sub-surficial (10-20cm) sediments were collected seasonally using vertical soilsampler from seven sites during winter, spring, summer, and autumn 2017. The study showed that the mean values of organic matter, organic carbon and total carbon, total nitrogen and total phosphorus were significantly increased (P