A contact switching device in which a movable iron core provided at one end portion of a movable shaft is attracted to a fixed iron core , based on excitation and degauss of an electromagnet portion , by which the movable shaft reciprocates in a shaft center direction, and a movable contact of a movable contact piece arranged at another end portion of the movable shaft contacts and departs from a fixed contact , wherein two coil springs different in diameter are put on the movable shaft, and one of the coil springs is arranged inside the other coil spring, comprising a housing formed by a case and a cover assembled to the case , the housing accommodating a contact mechanical portion in a sealed space and an electromagnet portion configured to drive the contact mechanical portion from an outside of the sealed space , wherein the contact mechanical portion and the electromagnet portion are integrated, the contact mechanical portion being made up of a magnet holder , the fixed iron core , the movable iron core , the movable shaft , the movable contact piece and a lid body , characterized in that the sealed space being defined by a metal frame body , a ceramic plate , a metal cylindrical flange , a plate-like first yoke and a bottomed cylindrical body , buffer materials are each made of an elastic material, pressed into depressions of the magnet holder and sandwiched between the magnet holder and a plate-like first yoke , wherein the magnet holder has a box shape that can be contained inside a metal cylindrical flange , is formed of a thermally-resistant insulating material, and is formed with pocket portions capable of holding permanent magnets on opposed both outer side surfaces, respectively, the plate-like first yoke has a plane shape that can be fitted in an opening edge portion of the case , and is provided with a fitting hole in a center thereof, an upper end portion of the cylindrical fixed iron core being brazed to the fitting hole by a brazing material , and a spring constant of the coil spring pressed subsequently during operation is made larger than a spring constant of the coil spring pressed first. wherein two coil springs different in diameter are put on the movable shaft, and one of the coil springs is arranged inside the other coil spring, comprising a housing formed by a case and a cover assembled to the case , the housing accommodating a contact mechanical portion in a sealed space and an electromagnet portion configured to drive the contact mechanical portion from an outside of the sealed space , wherein the contact mechanical portion and the electromagnet portion are integrated, the contact mechanical portion being made up of a magnet holder , the fixed iron core , the movable iron core , the movable shaft , the movable contact piece and a lid body , characterized in that the sealed space being defined by a metal frame body , a ceramic plate , a metal cylindrical flange , a plate-like first yoke and a bottomed cylindrical body , buffer materials are each made of an elastic material, pressed into depressions of the magnet holder and sandwiched between the magnet holder and a plate-like first yoke , wherein the magnet holder has a box shape that can be contained inside a metal cylindrical flange , is formed of a thermally-resistant insulating material, and is formed with pocket portions capable of holding permanent magnets on opposed both outer side surfaces, respectively, the plate-like first yoke has a plane shape that can be fitted in an opening edge portion of the case , and is provided with a fitting hole in a center thereof, an upper end portion of the cylindrical fixed iron core being brazed to the fitting hole by a brazing material , and <EOS>