A 69-year-old female complained of persistent abdominal pain, and annular ulcers and ulcer scars were detected endoscopically in the cecum. Pathological findings included caseous granulomas with some Langhans giant cells, and Ziehl-Neelsen staining was negative. Mycobacterium gordonae (M. gordonae) was identified by the DNA-DNA hybridization method and culture (Ogawa medium) of biopsy samples from ulcerous cecal lesions. After 6 months of antibiotic therapy, ulcerous cecal lesions were healed, and no acid-fast bacteria were detected by culture of biopsy samples from scar tissue. We believe this is the first report of M. gordonae infection in the alimentary tract.