The present study was designed to investigate the parasitic crustaceans affecting Seabass (Dicentrarchus labrax) and White grouper (Epinephelus aeneus) which collected seasonally from different areas of Mediterranean sea region (Port Said province). No pathognomic signs were detected in the infested fishes. Some revealed signs and P.M. lesions as sluggish movement, bulging of opercula, marbling (mosaic) appearance. Gills showed areas of thickened mucus and petechial hemorrhages and emaciation. The crustacean parasites were identified as copepods of Lernanthropus kroyeri  and Caligus minimus in D. labrax and isopods of  Praniza larva in E. aeneus. The total prevalence of crustacean infestations among seabass D. labrax was (36%) while in White grouper E. aeneus was (18%). The autumn and spring displayed the highest seasonal prevalence in seabass and grouper respectively. The relation between fish body weights, lengths and infestation rate were also studied.