Freshwater mussels are highly impacted by many human activities. As a result, it is considered one of the most threatened ecosystems worldwide. Studying genetic diversity is crucial for any further research on conservation efforts. In the present study, inter simple sequence repeat (ISSR) marker analysis was employed to study genetic diversity between 8 randomly selected specimens of bivalve. A total of 53 bands were produced from the 10 primers. Of these 37 bands were polymorphic, resulting in 69.8% polymorphism. Some primers showed more polymorphic bands than others. For example, primer ISSR M17 produced no polymorphic bands. While primer ISSR M1 produced 3 polymorphic bands (100% polymorphism). Cluster analysis, based on a similarity matrix, obtained showed that the 8 bivalve specimens can be clustered into two groups, one group containing specimens 2 and 6, and the other group representing specimens 4, 5, 1, 3, 7, and 8.   These data may suggest that the bivalves in Abohomos, Behera Governorate, Egypt, may have more than one species. The implication of these data on the conservation of the bivalve is explained. The conclusion is that the bivalve population has enough genetic diversity. These populations are adapted to the environment they live in and to the climatic changes.