Context: A comparatively small number of species, e.g., Vibrio parahaemolyticus and V. vulnificus , cause disease in both aquatic animals and humans. V. harveyi is marine animal pathogen and rarely causes infections in humans; however, it might become a reservoir of antibiotic-resistant bacteria forms and virulence genes. Aims: 1) to develop rapid multiplex polymerase chain reaction (PCR) assay for the simultaneous detection of V. harveyi, V. parahaemolyticus , and V. vulnificus by using vhhP2, tl , and rpoS genes as the respective target genes and 2) to evaluate specificity and determined detection of multiplex PCR technique. Materials and Methods: The multiplex PCR assay was developed and evaluated for specificity on 36 isolates of V. harveyi , 30 isolates of V. parahaemolyticus , and 14 isolates of V. vulnificus , along with other species of Vibrio and non- Vibrio bacterial isolates. Sensitivity of test was described as detection limit of pathogens in lowest amount of sample (CFU/mL or CFU/g) was determined by diluted DNA extracts of the pure cultures and spiked pacific white shrimp (Litopenaeus vannamei) samples Results: This developed multiplex PCR was proved as an accurate method, which was specific for three Vibrio species. The detection limits of V. harveyi , V. parahaemolyticus , and V. vulnificus in pure cultures and spiked shrimp samples ranged 1.05-4.8 × 10 3 CFU/mL and 1.9-7 × 10 4 CFU/g, respectively. Conclusions: This rapid multiplex PCR assay can decrease amount and process of sample preparation, which was time-consuming, and had preferable accuracy. This developed technique will be suitable and useful for food-borne pathogen detection in shrimp and horizontal gene transfer study among different Vibrio species in aquatic animals.