BACKGROUND Mycoplasma hominis brain abscess is a rare occurrence, and treatment is not well defined. The mechanism by which M. hominis infects sites outside the genitourinary tract, including the central nervous system, is unclear. METHODS We report the case of a 40-year-old Somali man who sustained a traumatic brain injury that required initial neurosurgical hematoma evacuation and that subsequently was complicated by a hospital-acquired M. hominis brain abscess. Our patient was successfully treated with neurosurgical debridement and an antibiotic course of intravenous doxycycline. CONCLUSIONS Head trauma or neurosurgical procedures or both might be a predisposing factor for this type of infection.