Parvimonas micra is a non-spore-forming anaerobic gram-positive coccus, widely distributed as normal flora in the skin, vagina and mucosa, and able to cause opportunistic infections, particularly endocarditis and brain abscess following dental manipulations. A 49-year-old woman was hospitalized due to fever and headache. She had been diagnosed with periodontitis at the beginning of fever. A brain abscess was noted in the right temporal lobe on the brain CT, and she was treated with ceftriaxone, isepamicin and metronidazole. In the next day, abscess was aspirated and drained by a surgical procedure. An organism was isolated from an anaerobic culture of the abscess aspirate, and was identified as P. micra by a commercial kit and 16S rRNA sequencing. (Korean J Clin Microbiol 2009;12:129-132)