The treatment for bilateral testicular tumors is associated with infertility and hypogonadism. We carried out testis-preserving therapy treatment for three patients with synchronous bilateral tumors with seminoma. Our protocol of testis preservation consisted of unilateral orchiectomy for the larger tumor followed by three courses of chemotherapy with a cisplatin, etoposide and bleomycin regimen. All three patients showed no recurrence 24, 24, and 82 months after treatment. The serum testosterone level was maintained around the lower limit of the normal range in all patients without androgen replacement, and sexual function was not impaired. One patient showed oligospermia, preoperatively, and the number of sperm was preserved at a similar level after treatment. Azoospermia was observed in two patients before the treatment, and still persisted after treatment. Testis preservation with a chemotherapy-based new protocol was carried out successfully without recurrence. In addition, our protocol preserved a good quality of life in all patients.