The present investigation was undertaken to study the occurrence of V. parahaemolyticus in shellfish and to assess the genomic diversity within V. parahaemolyticus strains isolate using ERIC-PCR technique. A total of 130 samples of shellfish were collected from fish markets, Zagazig city included white shrimps (40); blue crabs (40) and mussels (50).V. parahaemolyticus were isolated and identified using standard bacteriological methods.ERIC-PCR was carried out for a total of 9 V. parahaemolyticus clones, representing white shrimp, blue crab and mussels (3 each).V. parahaemolyticus were isolated with the percentages of 17.5(7/40), 12.5(5/40) and 16.0(8/50), respectively. The overall percentage of the examined shellfish was 15.4(20/130).Overall, the ERIC-PCR results showed 6 separate clusters at similarity level 0.53. Isolates No 4, 2, 5, 3 grouped together (group I). Isolates No 1, 8, 9, 7 and 6 each clustered in their own groups (II, III, IV, V and VI, respectively). In addition, there is sub-clustering with group I at similarity level 0.66. The amplified bands were analyzed by dendrogram using Dice correlation coefficient. The phylogenetic analysis of tested strains exhibits high amount of heterogeneity.It could be concluded from the present study that V. parahaemolyticus are circulating among the marketed shellfish in Zagazig city. Variable V. parahaemolyticus clones indicate different sources of contamination and infections under the research conditions.