Medical treatment for cancer is a combination of operative treatment, ra-diotherapy and chemotherapy. Theoretically, anticancer agent can kill can¬cer cells. However, it also causes many side effects especially on the normal cells, which have high mitosis activity. One of them is spermatogenic cell. Anticancer agent is included into reproductive toxin. Its working mecha-nism is by the alkylation of biologic molecules. Radiotherapy and chemotherapy reduce the number of spermatogonia Al, spermatogonia B and cause aberation of DNA structures on the next-generation cells including spermatozoa, hence result in the decrease of number of spermatozoa and sperm motility and the increase of the percentage of spermatozoa with abnormal morphology. The effects of radiotherapy and chemotherapy are temporary and reversibel. The cell recovery depends on the type of anticancer agent, its dosage and the length of therapy applied. Spermatogonia stem cells are the most important factors on this process.