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Seasonal abundance, biomass, and taxonomic composition of copepods in El-Mex Bay (Southeastern Mediterranean region) were studied from autumn 2011 to 2012. Most species within the copepod communities displayed a clear pattern of succession throughout the investigation period. Generally copepods were the predominant group. They contributed numerically 57% of the total zooplankton counts with an average of 5083 organisms/m 3 and a total number of 203,333 individuals. The bay harbored 50 species belonging to 28 genera within 19 families and 4 orders under one class. Calanoids were represented by 24 species which formed 31.6% of total copepods predominantly Acartia clausi , Calocalanus pavo , Clausocalanus furcatus , Eucalanus crassus , Nannocalanus minor , Paracalanus parvus , Eucalanus subcrassus , and Temora longicornis . Cyclopoids comprised 13 species of which Acanthocyclops americanus , Halicyclops magniceps , Oithona attenuata , and Oithona nana were the most abundant adult copepods. Eleven Harpacticoid species were also recorded with Euterpina acutifrons , Microsetella norvegica , Onychocamptus mohammed being the most prevalent. It was found however, that two Poecilostomatoida species were rarely encountered in the plankton Oncaea minuta and Corycaeus typicus . Copepod larvae and copepodite stages formed the main bulk of copepod Fauna as noticed in the El-Mex Bay during the investigation period. Their percentage was 36.7% of the total count and their total numbers were 74,629 individuals with an average of 1866 organisms/m 3 . The persistent relationships between total copepod counts, copepod orders, and physico-chemical variables suggested that physical factors operate on the copepod communities, either directly to limit maximum distribution along the bay, or indirectly on abundance.