Understanding of fish genetic characterization plays a vital role in the conservation and utilization of fish genetic resources of grouper species. The present study was carried out to assess the genetic diversity and phylogenetic relationships in five grouper species,
Epinephelus
spp. from eastern Saudi Arabian coast using two molecular marker systems, inter simple sequence repeat (ISSR) and microsatellite (SSR) markers. In total, 219 individuals grouper specimens (
Epinephelus tauvina, E. coioides, E. bleekeri, E. malabaricus, and E. areolatus
) were genotyped with 10 ISSR and 11 SSR selected primers. The ISSR produced 94 DNA fragments, of which 44 were polymorphic with an average of 2.13 fragment per primer. While SSR primers generated 107 alleles, all of them were polymorphic with an average 9.72 per primer. ISSR and SSR techniques demonstrated a high level of gene diversity and genetic distances illustrated by UPGMA dendrograms among the grouper species. The results proved that the SSR markers were highly informative and efficient in detecting genetic variability and relationships of the
Epinephelus
spp.