Streptococcosis caused significant economic losses for fish farming industry in the world. Six different streptococcus species are considered potential ?sh pathogens: Lactococcus garvieae, Lactococcus piscium, Streptococcus iniae, Streptococcus agalactiae, Streptococcus parauberis and Vagococcus salmoninarum. Information on the characteristics of streptococcal clinical isolates from red tilapia cultured in Mekong Delta, Vietnam is limited. The aim of this study was to access the prevalence and genotypic diversity among streptococcal clinical isolates recovered from cultured red tilapia in Mekong Delta, Vietnam. The present study provides useful molecular information for streptococcal clinical isolates in Vietnam compared with those from different hosts and geographic locations.