Testicular cancer is the most common tumor in young men. Bilateral testicular cancer is % 5 of all cases. About % 35 of these diagnosed with synchronous tumors and % 65 diagnosed with metachronous tumors. The incidence of contralateral testicular intraepithelial neoplasia is 4.9% and can be treated by low dose radiotherapy. Testis sparing surgery is an option only in selected cases. In this study we discussed all aspects of bilateral testicular germ cell tumors.