The gram-negative bacillus Yokenella regensburgei (of the Enterobacteriaceae family) can be found in groundwater and foodstuffs, as well as the digestive tracts of insects and reptiles. Although it has been isolated from humans since its original description, it has rarely been reported as a cause of infection, and then, only in immunosuppressed patients. We report the first case of post-surgical secondary osteomyelitis due to Y. regensburgei in an immunocompetent woman who had undergone a craniotomy.