To provide an air-feeding damper in which a complete closed state can be realized, a degree of aeration can be preferably controlled, and abnormal state is hardly produced even under an expansion or shrinkage caused by variation in temperature.

An air-feeding damper 1 comprises a frame means 5 having a passage 4 including an inlet hole 2 and an outlet hole 3, so as to cause the inlet hole 2 and the outlet hole 3 to be communicated to each other; fins 6 arranged within the frame means 5 so as to open or close the passage 4; and a rotation moving means 7 supporting the fins 6, rotating the fins 6 and generating an axial motion at the fins 6 through this rotation. The frame means 5 is provided with right and left side wall members axially oppositely arranged to each other so as to define the passage 4, wherein one of the right and left side wall members has a resilient closing member in opposition to the end surfaces of the fins 6 positioned at the side wall member. The end surfaces of the fins 6 are rotated by the rotation moving means 7 in such a way that the fins 6 may close the passage 4, axially moved and abutted against the resilient closing member before it may completely close the passage 4.