A case of bilateral testicular germ cell tumors of different cell types and maturation in the metastatic region is described. A 42-year-old man with bilateral testicular swelling visited our clinic. Bilateral high orchiectomy was performed. Subsequent histological examination revealed seminoma and embryonal carcinoma in the right testis and seminoma and mature teratoma in the left. Then bilateral retroperitoneal lymphadenectomy was performed and 7 metastatic regions were found in the para-aortic lymph nodes. One of these revealed histopathologically a mature teratoma containing cartilage constituents. After the operation, multiple drug treatment with Cis-DDP, vinblastine and pepleomycin was started. The patient has been in complete remission for about 1.5 year. In addition, we reviewed the literature about bilateral testicular germ cell tumors and maturation in the metastatic region.