PROBLEM TO BE SOLVED: To provide an environment harmonious-type gas-insulated apparatus for electric power capable of removing CO gases generated by reduction of a COgas in a gas-insulated apparatus for electric power using the COgas as an insulation medium and allowing safe maintenance and inspection.SOLUTION: The gas-insulated apparatus for electric power of an embodiment is configured in such a way that a carbon dioxide gas or a mixed gas containing the carbon dioxide gas is filled, as an arc-extinguishing gas, in a hermetically sealed container, and a pair of contacts are disposed inside the hermetically sealed container. At electricity conduction time, both are maintained in a contact state to establish electricity conduction, and at electricity cutoff time, the contacts are separated to generate an arc discharge in the insulation gas, and a current is cut off by extinguishing the arc discharge. A metal oxide is disposed at a place in the hermetically sealed container contacted by a heat flux arising from the arc discharge.