Four cases of central granular-cell tumor of the jaws were evaluated to determine the clinical parameters of the lesion, and one of these cases was examined with the electron microscope to investigate the nature of the granular cells. The average age of the patients at the time of treatment was 55 years; all four patients were women. Three of the lesions originated in the mandible, and one in the maxilla. Follow-up studies revealed no recurrences. Electron microscopic examination of one case revealed that the granular cells contained many lysosome-like particles and that these cells are identical to those found in the granular-cell myoblastoma.