Studies were undertaken to isolate and characterize vibrio species pathogenic to fish. Thirty six vibrio- like isolates were obtained from twenty one of 160 fish samples. Biochemically the collected isolates were identified as Listonella an-guillartn biotype B and C, Vibrio alginolyticus and unidentified lactose-fermenting vibrio spp. Eight vibrio strains of different origins were selected and were grown onto tryptose soya agar with 5% sheep blood for preparation of outer membrane proteins (OMPs). The OMP profiles of the tested strains were separated using sodium dodecyl- sulphate polyacrylamide gel electrophoresis (SDS- PAGE). Dice index of similarity was determined with each strain. Analysis of OMPs showed that the local vibrio strains had 8-9 protein bands of molecular weight ranging from 19.7- 212.9 KDa and they contained three major protein bands of molecular weight 19.7, 36 and 80 KDa. Moreover, SDS - PAGE analysis?' of the local vibrio strains indicated OMP expression differences in protein between strains defined mu- tant and within the same species strains belonging to different biogroups possessed distinct electrophoretic banding proteins. In conclusion SDS-PAGE analysis of OMPs may be considered as sensitive, reliable and rapid diagnostic method to characterize vibrio isolates.