A monitoring program to follow vibriosis incidents in the Greek marine aquaculture was implemented over the past 13 years. 273 isolates, from various cases originating from eight regions and nine hosts, were collected and characterized. The main aquaculture species of the survey were the European seabass (Dicentrarchus labrax) and the gilthead seabream (Sparus aurata). Various species ofVibrionaceaewere associated with vibriosis.Vibrio harveyihad the highest prevalence and was isolated throughout the year from all hosts. During the warm months,Vibrio harveyiprevailed with frequent co-isolations ofPhotobacterium damselaesubsp.damselaeandVibrio alginolyticus, while during spring, otherVibriospecies were more abundant, such asVibrio lentus, Vibrio cyclitrophicus,andVibrio gigantis.Phylogenetic analysis using themreBgene and the metabolic fingerprint of the isolates showed great variability within the species of the collection. The severity of the disease and the frequency of outbreaks make vibriosis (that is, mainly attributed toV. harveyi) an important concern for the regional aquaculture sector.