Campylobacter fetusis a zoonotic pathogen that occasionally causes serious, relapsing, invasive disease, especially in immunocompromised hosts. We report a case of relapsingC. fetusdiarrheal illness in a 75-year-old woman which resulted in secondary bacteremia and seeding of the left knee prosthetic joint. Patient responded favorably to debridement and retention of prosthesis in addition to six weeks of meropenem followed by chronic oral doxycycline suppressive therapy.