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In this paper the integrated chemistry-climate model (RegCM4-CHEM) was used to study the characteristics of the simulated pollutants and atmospheric conditions over Egypt with a focus on the Nile Delta (ND) region. The densely populated ND region is known for its severe air quality issues driven by high levels of anthropogenic pollution in conjunction with natural sources such as dust, and agricultural burning events. The data used in our study is from Monitoring Atmospheric Composition and Climate reanalysis data (2003-2010) and from the RegCM4-CHEM model simulation (2001-2010) over Egypt. It is found that surface ozone (O 3) has higher values during the period from May to September that indicates their sensitivity to temperature and sinking air above the subtropical high pressure during these hot months. Higher values of carbon monoxide (CO) occur in winter associated with the largest amounts of fuel burning in winter. The higher values of formaldehyde (HCHO) occur in summer associated with high temperatures and an abundance of OH (hydroxyl radical). The higher values of NOy appear in summer months, September and October in the layer between 1000 and 300 hPa, it is in the upper layer is generally greater than in the middle because it contains nitrogen oxide (NOx), which regarded as a catalyst in O 3 loss and production.