While soft tissue tumors can occur in the penis, corpus cavernous tumors are rare. Reported cases of corpus cavernous tumors are from metastases of advanced malignancy, such as cancers of the bladder, prostate, rectosigmoid colon, kidney, pancreas, liver, testis and nasopharynx. Primary corpus cavernous tumors are extremely rare and have possibly never been reported before. Herein, we report a case of leiomyoma of the corpus cavernosum. After the diagnosis of leiomyoma was established, total excision of the tumor was not attempted and the tumor remained unchanged in size and shape over a follow-up period of 15 months.