To provide a heat exchange device capable of adequately heating or cooling sealed fluid in each packaging bag while carrying individual packaging bags.

A plurality of steel belt conveyors 2, 2, etc. to carry a packaging bag H with the packaging bag H placed on an upper surface part 2a are arranged in a multi-stage manner. A plurality of press rollers 4, 4, etc. are arranged above the upper surface part 2a of each steel belt conveyor. A guide means 3 to guide the packaging bag H unloaded from an unloading end 2h of one steel belt conveyor 2 to a load-receiving end 2g of the other steel belt conveyor 2 is provided between one unloading end 2h of the steel belt conveyors 2 and 2 adjacent to each other in the information direction and the other load-receiving end 2g. A heating or cooling means 12 of a steel belt 2f to constitute the steel belt conveyor 2 is provided.