A first case of subdural empyema due to .

, an anaerobic coagulase-negative staphylococcal species, is a member of the normal skin microbiota. It can be a rare cause of human infectious disease and is usually considered a contaminant, but some rare reports have described deep-seated infections caused by . Intracranial subdural empyema, a life-threatening condition that requires early diagnosis and emergency intervention, can be caused by various pathogens. A 54-year-old man with no pre-existing medical conditions other than hypertension was transferred to our emergency department because of progressively worsening consciousness impairment. As non-contrast head computed tomography revealed hematoma-like collection in the subdural space, urgent drainage was performed via multiple burr holes. Perioperative tissue culture yielded monomicrobial growth of after 4 days. Meropenem was administered in the immediate postoperative period, and later replaced with Penicillin G for six weeks. The patient is now in good clinical condition more than 18 months after treatment. This represents the first reported case of subdural empyema caused by in an immunocompetent adult patient with a review of the pertinent literature. should be added to the list of anaerobic microorganisms that can to cause subdural empyema. Prolonged anaerobic culture is critical to improve the yield of this possibly underestimated pathogen.