The dietary supplement, POLY-MVA, containing palladium alpha-lipoic acid complex was examined for its efficacy as a radioprotector in mice exposed to whole-body gamma-radiation. Oral administration of POLY-MVA enhanced endogenous spleen colony formation in animals exposed to a sublethal dose of 6 Gy gamma-radiation. Alkaline comet assay revealed that the nuclear DNA comet parameters such as percent DNA in tail, tail length, tail moment, and olive tail moment, of the bone marrow cells and spleen cells, were found increased following whole-body gamma-irradiation. The radiation-induced DNA damage in these cells was reduced when POLY-MVA was administered to animals exposed to a lethal dose of 8 Gy whole-body gamma-radiation. The administration of POLY-MVA significantly reduced the gamma-radiation-induced mortality and also aided recovery from the radiation-induced loss of body weight in mice surviving after 8 Gy gamma-radiation exposure. These results suggest the potential use of POLY-MVA as a radioprotector in cases of planned radiation exposures.