DUCT STRUCTURE

A duct structure having excellent sealing performance at a connection portion between a duct and a piping member. The duct structure includes a duct and a piping member. The duct includes an opening in a tubular portion, and the piping member includes a piping portion. The piping portion is inserted into the opening and connected to the duct, and a foam rubber sealing material is disposed in a compressed state between an outer peripheral surface of the piping portion and an edge of the opening.