Tuberculosis cutis orificialis (TCO) is a rare manifestation of cutaneous tuberculosis that is caused by auto-inoculation of mycobacteria in patients with advanced internal tuberculosis. TCO occurs in oral, perianal, or genital mucosa and adjacent skin. The tongue is the most frequently affected site, but the perianal area can also be affected. A 39-year-old male presented with a 4-month history of painful ulcers on the perianal area. The histopathologic findings revealed granulomatous infiltrates composed of epithelioid cells and Langhans-type giant cells in the dermis, and a few acid-fast bacilli noted on Ziehl-Neelsen staining. The polymerase chain reaction (PCR) was positive for Mycobacterium tuberculosis and the chest X-ray showed findings consistent with active pulmonary tuberculosis in both upper lung zones. The skin lesion showed complete resolution 2 months after the start of treatment with antituberculosis agents. We report a case of TCO with perianal involvement in a patient with underlying active pulmonary tuberculosis. (Ann Dermatol 21(4) 443∼446, 2009)