Exocellular proteases produced by Vibrio fluvialis, V. furnissii, V. metschnikovii and V. campbellii were characterized and compared to those of V. mimicus protease (VMP) and V. vulnfcus protease (VVP). These proteases possessed both elastolytic and hemagglutinating abilities and were identified, except that of V. metschnikovii, as metalloprotease. Conversely, V. metschnikovii protease failed to exhibit some of the salient features for metalloproteases suggesting the existence of protease(s) other than metalloprotease. However, antibodies against VVP cross-reacted to these proteases and to VMP indicating antigenic relatedness amongst vibrio proteases. This study, thus, demonstrated the prevalent distributions of antigenically related proteases both in pathogenic and non-pathogenic vibrios, bringing their status as a virulence determinant into question.