Aeromonas hydrophila is a gram-negative organism that is the causative agent in several clinical infections. Although it has been reported to cause osteomyelitis in immunocompromised patients, it has not been reported to cause this in the normal host. We describe two patients in whom acute osteomyelitis developed following trauma in freshwater lakes. Cultures yielded A hydrophila, and both patients responded to a two-week course of parenteral antibiotics followed by oral tetracycline hydrochloride in the outpatient setting. Since A hydrophila is a common inhabitant of freshwater lakes, it should be suspected in infections occurring in this epidemiologic setting.