Yersinia enterocolitica is a gram-negative coccobacillus. Y. enterocolitica infection is acquired by humans via the oral route. Infection due to Y. enterocolitica was first observed in 1933 in New York. Y. enterocolitica septicemia has been increasingly recognized in recent years, whereas endocarditis due to Y. enterocolitica is a rare manifestation. We herein describe a patient who developed Y. enterocolitica endocarditis and was successfully treated with a combination of drugs consisting of a quinolone (ofloxacin) and an aminoglycoside (netilmicin).