A 38-year-old woman was referred for urethral tumor treatment. Needle biopsy of the tumor was performed. Histologically, the tumor was composed of large polygonal cells with eosinophilic and periodic acid-Schiff (PAS)-positive granular cytoplasm, indistinct cell margins and small round central nuclei. Immunohistochemical staining for S100 protein, vimentin, and neuron-specific enolase (NSE) was positive, indicating that it was a granular cell tumor. Excision of the tumor including the urethra and appendicovesicostomy using the Mitrofanoff principle were performed. There has been no tumor recurrence in the 8 months after the operation.