We retrospectively analyzed 163 patients who had been cryopreservating their sperm one year or more. They consisted of 72, 76 and 15 patients with a germ cell tumor, hematologic cancer and other diseases, respectively. Forty-eight patients (29.4%) were still cryoperservating their sperm, and the average period of cryoperservation was 4.7 +/- 3.0 years (1-13.1 years). Only 6 patients (3.7%) had used their cryopreserved sperm and the average preserved period was 6.0 years (1.3-12 years). In 115 of the 163 cases, the cryopreserved sperm was abandoned, and the main reason was the recovery of spermatogenesis. Of the cases that underwent semen analysis after treatment, 20.9% of the patients with testicular cancer and 57.9% of the patients with hematologic cancer, have not recovered spermatogenesis. Because chemotherapy to the testicular tumor and leukemia risk injuring testiclar function, cryopreservation of the sperm before treatment should be recommended. Because the preservation period tends to be prolonged, development of a system for long-time preservation is awaited.