A throttle body of an electrically controlled throttle apparatus is constructed with a bore wall part, a motor housing part receiving a heavy component such as a motor and a connecting member that connects the bore wall part and the motor housing part with each other. The bore wall part has a cylindrical inner periphery for rotatably receiving a circular-shaped throttle valve. The connecting member is constructed with plural plate-shaped ribs. Thus, the connecting member can be rigid without becoming a thick member. Therefore, the connecting member can be restricted from contracting in its molding process, so that circularity of the cylindrical inner periphery of the bore wall part can be maintained. Thus, the cylindrical inner periphery of the bore wall part can rotatably receive the circular-shaped throttle valve without arising interference against each other, and airtightness of the throttle valve can be maintained, when the throttle valve is in the full close position.