To provide a lightweight resin air volume control device which can prevent sticking between a throttle body and a throttle body, that possibly occurs in early morning in a cold district or during a cold start of an engine, so as to allow the operation of the throttle valve to be satisfactory.

In a resin air volume control device composed of a throttle body 2 and a throttle valve 3 which are formed of a composite material containing synthetic resin as a matrix, opposed bearings 8 which are provided to the peripheral wall part of the throttle valve 3, a throttle shaft 6 journalled by the bearings 8, the throttle valve 3 fixed to the throttle shaft 6 being rotatable around the axis of the throttle shaft 6, at least an outer peripheral part 3c of the throttle valve 3 opposing the throttle body, and/or at least an inner peripheral part 2c of the throttle body 2 opposing the throttle valve 3 are made of a composite material containing 0.1 to 10 weight parts of an oil component with respect to 100 weight parts of the matrix synthetic resin.