When ionizing radiation comes to interaction with a human body, it can have extremely damaging impact on it. Chemical radioprotectors are used as a radiation countermeasures, reducing the harmful effects of ionizing radiation. They have a wide range of application, ranging from protection of normal tissues of cancer patients during radiotherapy, to safeguard people after radiological or nuclear accidents. Despite testing a large number of natural and syntetic compounds, only a few have found its place in clinic with limited tolerance. Therefore understanding the mechanisms of radioprotection is necessary in the development of more suitable and customized radiatioprotectors. Optimal radioprotection in the future can be achieved by a combined treatment regimen including subtoxic doses of one or more radioprotectors in combination with good nutrition, vitamins and immunomodulators.