Granular cell myoblastomas from 42 patients were examined microscopically, and the regional distribution of the 52 lesions is illustrated. The clinical records of the patients in this series showed an average age incidence of 37 years, a greater frequency among Negroes (74%) and in females (67%), and a rather high rate of multicentricity (14%). Only one of the patients had a recurrence following primary excision. None of the lesions underwent a malignant change. The possibility of a viral factor in the pathogenesis of these lesions is briefly discussed.