Campylobacter fetus is a fastidious, curved, Gram-negative bacillus that has been increasingly associated with human disease. To our knowledge, we are reporting the first documented case of C fetus sepsis associated with an aortic mycotic aneurysm. Typical of previously reported cases of infections caused by this organism, this case involved a debilitated patient who was seen initially with a subacute febrile illness associated with bacteremia, but who died suddenly when the unsuspected aneurysm ruptured. The isolate was presumptively identified by its growth characteristics, motility, curved shape, and the presence of a single polar flagellum.