Marina El-Alamein is one of the biggest tourist summer resorts at the north coast of Egypt. This was the first tourist project in the northern Sahel region bordering the Mediterranean Sea in Egypt. The present study is the first attempt to provide data on hydrography and plankton community structure of the coastal and lake waters of Marina El-Alamein tourist resort. Samples were collected seasonally from 10 stations in the study area during 2017. Forty five phytoplankton taxa included within five groups were identified during the present survey. Bacillarophyceae was the most diversified phytoplankton group (28 taxa) followed by Dinophyceae (7 taxa), Chlorophyceae (5 taxa), Cyanophyceae (3 taxa), and Euglinophyceae (2 taxa). The highest phytoplankton abundance was 4.44×10³ unit/l in summer and the lowest value was 3.55×10³ unit/l in winter with an annual average of 4.03×10³ unit/l. Zooplankton community in the study area comprised 14 species; 4 Protozoa, 4 Copepoda, 3 Rotifera, besides one species of cnidarian, one ostracod and one of molluscs. The meroplanktonic larvae of polychaetes, decapods and molluscs were also recorded. The lowest zooplankton abundance was recorded during winter (aver. 0.9×10³ind.m^-3) while the highest abundance was recorded during autumn (aver. 27.6×10³ind.m^-3).  Copepoda was the highest abundant group (81.77% of the total zooplankton crop) followed by Rotifera, the meroplanktonic larvae of Mollusca and Polychaeta. Finally, it would be concluded that the plankton community structure in Marina El-Alamein area represents a balanced and stable marine ecosystem. This is probably due to the exchange of waters between the Sea and lagoon and good environmental management of the lagoon by the concerning authorities.