Vibrio vulnificus is an opportunistic pathogen widely distributed in estuarine and coastal seawaters. In this study, a culture-free method was developed to rapid detection of V. vulnificus in all seasons, based on loop-mediated isothermal amplification (LAMP) targeting virulent-correlated gene (vcg). The new assay method allows differentiation between the virulent and non-virulent strain of V. vulnificus accurately. This method also allows effective detection of the pathogeny in winter when the bacterium lives in the viable but non-culturable (VBNC) state. A total of 30 costal seawater samples collected in all seasons were used for the evaluation of this method. The results show that the method is sensitive, accurate and convenient.