A switch device including arm springs as movable contacts slide in accordance with a switching operation of a switch knob. The arm springs come into resilient contact and slide on movable contact slide parts. Root parts and mountain parts are formed in the movable contact slide parts and a fixed contact is formed with end edges of bus bars. The bus bars are mounted and fixed to an upper surface of a support part. A cut out part is provided on the upper surface of the support part. The arm springs are formed in the shapes of bars having mountain forms in section fitted to the root parts, and the arm springs are extended in the vertical direction to plate surfaces of the bus bars and arranged to be inclined so that outer side surfaces abut on upper side edges of the fixed contacts.