An electrically controlled throttle apparatus is constructed with a throttle body and a throttle valve that are simultaneously molded of a resinous material in the same molding dies. The throttle valve is rotatably assembled in a bore wall part of the throttle body while the throttle valve is rotated by a predetermined rotation angle θ between 45° and 135° with respect to a rotation angle 0° corresponding to its full close position. An outer circumferential periphery of the filler, which is molded to be the throttle valve in a cavity of the molding dies, is compressed by a predetermined pressure when the throttle valve and the throttle body are molded. Thus, dispersion of contraction of the throttle valve can be reduced in its molding process by adding the compression process.