The utility model relates to an air heat exchanger, which is suitable for heating air by steam, hot water and heat conducting oil. Widely used in textile printing and dyeing (such as: setting machine, drying machine, printing machine and so on), chemical fiber, rubber, food, chemical industry, metallurgy, pharmaceutical, leather and plastic coating (such as: coating machine, coating machine, complex contract, spray coating machine, printing machine and so on), machinery, wood industry air heating or cooling