The article reviews the sixty-year activities of United Nation Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). The authors emphasize the unique role of this Committee in the expert evaluation, systematization and analysis of scientific data on the effect of ionizing radiation on human and the environment considering a wide range of the radiation levels (doses). The UNSCEAR materials are widely used in the elaborating measures for radiation protection and safety. They contribute to the expansion of the radiation technologies employment being focused on the ionizing radiation biological effects. The article shows the participation of the Republic of Belarus in the UNSCEAR operation.