This study aimed to determine the prevalence of V. alginolyticus isolated from mullet, seabream, and seabass marine fishes in addition to study the phenotypic and genotypic identification of the isolated strains. A total of 180 samples were examined bacteriologically for detection of V. alginolyticus. Six isolates were identified biochemically as V. alginolyticus (3. 33%).The highest prevalence of V. alginolyticuswas in seabreamfollowed bymullet and seabass in a percentage of 5.00% 3.33% and 1.60 % respectively. The highest prevalence ofV. alginolyticuswas isolated from liver and spleen with percentages of 50% in mullet fish. While in seabream fish the highest prevalence ofV. alginolyticuswas isolated fromliver andkidneywith percentages 66.67% and 33.33% respectively. On other hands the highest prevalence ofV. alginolyticuswas isolated fromliver of seabass fish samples in a percentage of 100%. PCR was used for confirmation of Vibrio spp. by detection of 16S rRNA andV. alginolyticusby detection of collagenasegene.All 6 isolates were positive for the16S rRNA andcollagenasegene which specific for V. alginolyticus.All V. alginolyticusisolates were tested for the detection oftdh and trhwhich is responsible for its virulence. The results showed that all V. alginolyticusisolates were negative fortdh and trhgenes.