Edwardsiella tarda has been regarded as s a notorious fish pathogen affecting diverse fish species around the world. Recent studies showed that E. tarda was phylogenetically re-classified as E. anguillarum, E. piscicida and E. tarda based on average nucleotide identity. In this study, we performed comparative genome analysis using hitherto sequenced genomes of strains belonging to the genus Edwardsiella. Thirty five hitherto sequenced genomes consisted of total of 10,002 protein-encoding genes, only 14.1% of the genes (1,443) were core genes, and the remaining 85.9% were dispensable and singleton genes within the genus. Pan development plot analysis showed that E. piscicida and E. anguillarum had open pan-genome, indicating that Edwardsiella spp. are adaptable to a variety of environments, and it is expected that the genes shared by species may be related to adaptation ability and species specificity. In addition, we attempted to re-identify 52 Korean isolates belonging to the genus Edwardsiella using our developed specific primers. As a result, 41 and 11 isolates were identified as E. piscicida and E. anguillarum, respectively. Serotyping were also performed with anti-sera that were prepared in rabbit with E. tarda ATCC15947, E. piscicida ETW41 and E. anguillarum EET61. Strains of E. piscicida and E. anguillarum were serologically grouped well, but E. tarda strains exhibited very low agglutination with all 3 anti-sera. This study shows that 3 Edwardsiella species were clearly distinguished from others, and most strains that were known as E. tarda were re-identified as E. piscicida or E. anguillarum. This result would provide very valuable information on species-specific control measures against Edwardsiellosis.