We report the case of a 67-year-old man who had an infection of a pseudoaneurysm of an aortic graft with contiguous vertebral osteomyelitis. The infectious organism was identified as Coxiella burnetii, a strict intracellular pathogen causing Q fever infection in humans. The patient was treated successfully with removal of the infected material in conjunction with extraanatomic bypass and specific antibiotic therapy. He is doing well after more than 3 years, with no evidence of recurrent periaortic infection on successive computed tomographic scans. We suspect that C. burnetii vascular graft infections could be underdiagnosed, because this cause is not frequently evoked. We suggest that extending the etiologic search to C. burnetii could decrease the number of undocumented vascular graft infections.