To provide a rotary switch device of such a structure that a rotor is supported turnably between a base member where a stationary contact is fixed and a case where a leg having a fitting pawl to be fitted to the base member at the tip is installed consolidatedly and that a movable contact biased by spring toward the base member is held by the rotor in levitation, wherein it is made possible to enhance the easiness in the installing works of the case to the base member, simplify the die configuration for molding the case, enhance the reliance upon the insulation, and mount the case on the base member certainly.

At the tip of a leg 66 furnished on a case 25 in such a way as inserted through a fitting hole 65 provided in a base member 56, a fitting pawl 67 is installed rigidly as protruding sideways to the outside from the tip of each leg 66, and a slipoff preventive part 125 fitted in the fitting hole 65 as interposed between the base member 56 and leg 66 is installed rigidly on a cover 28 covering at least the connection part of each conductor with a stationary contact on the other surface side of the base member 56.