To provide a regenerative air preheater in which choking or corrosion caused by low metal temperature can be avoided.

The regenerative air preheater 1 is roughly divided into two sections 9 and 10 each comprising a pair of gas sector 6 and an air sector 7. The gas sector 6 and air sector 7 of each section 9, 10 are arranged point- symmetrically to the element rotating shaft 1a of the regenerative air preheater 1. Respective sectors are arranged such that gas and air flow reversely in one section 9, 10 but flow in parallel in adjacent sections. Gas and air are fed to respective sectors 6 and 7 to face each other, respectively, from the opposite directions.