A granular cell tumor is a relatively rare benign tumor arising in various soft tissues of the body. In the oral region, it commonly occurs in the tongue. We report three cases of granular cell tumor arising in the tongue and the floor of the mouth.
　Case 1: A 33-year-old woman had an elastic-hard mass of 18×13mm in the left lateral border of the tongue. The tumor was excised with a 3-mm margin under general anesthesia.
　Case 2: A 35-year-old man complained of a small mass at the left lateral border of the tongue. The tumor was excised with a 3-mm margin under local anesthesia.
　Case 3: A 62-year-old woman had a small submucosal mass of 7×7mm at the left sublingual caruncle. The tumor was excised with a 3-mm margin under local anesthesia. In all cases, histopathologic examinations revealed granular cell tumor. There was no distinct capsule around the tumor. Tumor cells had intracytoplasmic granules immunostained with S-100 protein, NSE, CD68, Vimentin, and Galectin3. In cases 2 and 3, tumor cells were positive for Calretinin, suggesting neurogenic origin. We searched and discuss 130 cases of granular cell tumor reported in Japan.