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The cave barb habitat is located in a Karst formation along the Sezar River. The springs on the walls of the Sezar River valley may provide a means for fish in surface waters to penetrate into the underground waters. These observations propose the probability for a migratory relationship between Garra gymnothorax in the Sezar River and the cave barbs (Garra typhlops and Garra lorestanensis). In addition, a variety of different body shapes including fusiform and slender body forms are observed among the cave fish. This phenotypical variation may be a sign of an unknown genetic diversity or could be attributed to the variable environmental conditions in different parts of the subterranean habitat. To clarify the situation, we used the sequences of mtDNA cytochrome oxidase subunit I and next generation sequencing method. The results showed that the fusiform and slender body shapes of G. typhlops and G. lorestanensis were not different with regard to their mtDNA and genomic compositions. Moreover, the analysis of the genomic their mtDNA and genomic compositions. Moreover, the analysis of the genomic showed that a limited level of gene flow (less than 3%) from G. gymnothorax probably existed in G. thyphlops. The low level of gene flow may be related to the lower fitness and adaptability of the surface dwelling fish to the subterranean life conditions.