PURPOSE: To provide a processing method of air to be fed to a combustion engine effective to pollution prevention, saving of fuel sources and fuel economization in order to make fuel into a complete combustion and improve the extent of combustion efficiency,

CONSTITUTION: Magnetism of more than S-pole magnetism 300 gauss and less than 3000 gauss is attached to an air feed pipe in and around an engine and a boiler in making the S-pole magnetism side adhere close to it, through which air to be fed to these combustion machinery is made so as to be exposed under the magnetic atomosphere.