The diagnosis of isolated tuberculosis of the brachioradialis muscle without osseous involvement was made by excision of the lesion and histologic examination in a 72-year-old woman who was in a poor general state. The patient was free of other systemic symptoms or other foci of infection. The wound healed without complication with the aid of antituberculous chemotherapy. Two years later, the patient remains symptom-free with no signs of recurrence.