Background <p>Brain abscess caused by atypical pathogens presents significant diagnostic and therapeutic challenges. The unusual clinical presentations, coupled with incomplete or inaccurate patient histories, often result in misdiagnosis and inappropriate treatment.</p> Case presentation <p>We report a case of a retained intracranial bamboo foreign body resulting in a brain abscess. A female adolescent presented with a newly developed mass on the eyelid. Medical imaging identified a foreign body that had penetrated the frontal lobes via the transorbital route, leading to the formation of a brain abscess. The foreign body was successfully removed through transnasal endoscopy. Inflamed tissue adherent to the foreign body was cultured and analyzed using metagenomic next-generation sequencing (mNGS), which identified <i>Clostridium celerecrescens</i> as the causative pathogen. The patient fully recovered after surgical debridement and two weeks of antibiotic therapy.</p> Conclusions <p>Infections caused by <i>C. celerecrescens</i> are exceedingly rare in clinical practice. This case highlights the bacterium’s ability to adhere to a bamboo foreign body, leading to the formation of a rare brain abscess. mNGS proves to be a valuable diagnostic tool for identifying uncommon infectious agents.</p>