Objective To investigate the etiology of a small outbreak of gastroenteritis caused by Vibrio parahaemolyticus in Guangzhou, 2017. Methods Serotype identification, antimicrobial susceptibility test, polymerase chain reaction (PCR) test of virulence genes (tdh, trh, tlh), toxRS/new gene, orf8 gene, pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were analyzed. On the basis of epidemiological investigation, the serology, virulence, antimicrobial susceptibility and molecular characteristics of a total of 14samples Vibrio parahaemolyticus samples were tested.Results The serotype O8∶K21 of 14 strains of Vibrio parahaemolyticus was identified. All isolates were sensitive to ceftriaxone, ciprofloxacin, chloramphenicol, cotrimoxazole, sulfonamide complex, amikacin, nalidixic acid, streptomycin, tetracycline and gentamicin, and resistant to apart from ampicillin and trimethoprim. The PCR detection of virulence gene showed that all the strains were positive for tdh (thermostable direct hemolysin) and tlh (themolabile hemolysin), but negative for trh (tdh-related hemolysin), and carried toxRS/new and orf8 genes. According to PFGE cluster analysis, they were considered it was judged to be a highly related strains. According to MLST analysis, the results were all ST479 type. Conclusion The reason for the small outbreak of gastroenteritis was due to Vibrio parahaemolyticus O8∶K21, which shared common genetic characteristics. It harbored the Positive for both the tdh gene which was gene and group-specific polymerase chain reaction is the key characteristic of pandemic strains, and additional surveillance should be conducted to facilitate control of the transmission of this pathogen.