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<i>Enterococcus</i> spp. are pathogens that cause environmental mastitis and are difficult to eliminate owing to their resistance to antibiotics. To compare the virulence characteristics of isolates from bovine mastitis milk (BMM) and bovine normal raw milk (NRM), we isolated <i>Enterococcus</i> spp. from 39 dairy farms in South Korea from 2015–2020. A total of 122 <i>Enterococcus</i> spp. were identified, with <i>Enterococcus faecalis</i> (73.8%) accounting for the majority, followed by <i>Enterococcus faecium</i> (26.2%). <i>E. faecalis</i> isolated from BMM harbored <i>gelE</i>, <i>asa1</i>, <i>esp</i>, and <i>cylA</i> genes with a prevalence of 85.7, 71.4, 54.3, and 30.0%, respectively. These genes were significantly more abundant in BMM than in NRM, except for <i>asa1</i> (<i>p</i> < 0.0001). Interestingly, strong biofilm and gelatinase formation was predominately observed for BMM isolates and this was significantly correlated to the presence of <i>esp</i> and <i>gelE</i> genes (<i>p</i> < 0.05). BMM isolates demonstrated higher resistance to tetracycline (59.3%), followed by chloramphenicol (21.0%), rifampicin (18.5%), doxycycline (4.9%), ciprofloxacin (1.2%), and nitrofurantoin (1.2%), than those from NRM. <i>E. faecalis</i> harboring <i>esp</i>, <i>gelE</i>, and <i>cylA</i> may be causative agents for bovine mastitis and act as a reservoir for the transmission of virulence factors to humans.