Thanks to the successful screening programs, medical advances and new treatment protocols, the survival of patients with malignant diseases is prolonged and attention is being devoted to improving all forms of quality of life. Special attention is paid to the preservation of reproductive health. In order to preserve fertility, women use cryopreservation of embryos and oocytes, ovarian tissue cryopreservation with later retransplantation, ovarian suppression with gonadotrophin-releasing hormone (GnRH) agonists along chemotherapy, ovarian transposition at radiation therapy and ovarian donation, and even replacement motherhood. It is very important to have an individual approach in choosing the method to preserve fertility. The choise of method depends on the age of the woman, the chemotherapy protocol and the time remaining until the beginning of the treatment of malignant disease and existence of the partner at the time of the procedure of fertility preservation. Preserving the fertility of men is based on relatively simple and inexpensive methods. The standard method of preserving fertility in boys after puberty and adult men is cryopreservation of semen. The use of hormone therapy, or gonadotropin-releasing hormone (GnRH) agonist, did not prove to be an effective method. Early puberty boys have recommended testicular tissue cryopreservation, with an important note that it is still an experimental method. It is recommended that an oncologist and a human reproduction specialist participate in the discussion on fertility, along with the sufferers.