To provide an air intake duct manufactured easily, which is capable of reducing noises from an air intake port.

A sound absorbing material 20 made of nonwoven fabric is held between the abutting surface 13a of a first overhang section 13 integrally formed along the both side edges of a first duct forming member 11 and the abutting surface 16a of a second overhang section 16 integrally formed along the both side edges of a second duct forming member 12. Between both of the abutting surfaces 13a, 16a, a constant clearance is formed by the contact between the protruded piece 15 of the first duct forming member 11 and the protruded section 18 of the second one 12. The sound absorbing material 20 is held between both of the abutting surfaces 13a, 16a in an appropriately compressed condition.