The present invention provides a treating agent for a metal hydride-containing exhaust gas, wherein the treating agent is low in exothermic property and further high in performance in a treatment of harm-elimination for the metal hydride-containing exhaust gas, comprises at least one among metal hydroxide, metal carbonate, basic metal carbonate, and further supports at least one metal among group-VIII noble metals on periodic table and silver. Therefore, the performance of harm-elimination for the metal hydride-containing exhaust gas is prominently improved. The treating agent in the present invention is high in performance and further low in exothermic property, thereby that is useful in the treatment for the metal hydride-containing exhaust gas generated in semiconductor manufacturing industry and the like.