Abstract: The important role as played by the air preheater for energy saving of the steel tube heating furnace is discussed. The design, manufacture quality control and inspection methods, and installation of the preheater are described, covering such aspects as selection of thermal tool data, structure design and material selection. Also involved is how to operate and maintain the preheater appropriately. Following the method as mentioned here in the paper will result in such advantages as improving the combustion coditions, saving energy, reducing environment pollution as well as extending the service life of the preheater.