Two new Cyprinoid species are described from Phu Quoc Island, Gulf of Thailand. The first new species, Barbucca elongata sp. nova (Balitoridae), differs from the species B. diabolica, which is described previously, in more elongated body covered by small scales (50–67 perforated lateral line scales), conical snout, and coloration. The second new species, Rasbora vietnamensis sp. nova (Cyprinidae), belongs to the species group “R. trifasciata”; it differs from other species of the group in substantially reduced lateral line system with four-seven perforated scales and absence of red pigmentation on the fins and body.