To provide an incomplete combustion reduction sheet capable of improving a global environment and enhancing a cost reduction effect in social problems by the synergistic effect of the sheet which is useful for reducing exhaust gas and increase fuel economy in combustion apparatuses.

An incomplete combustion reduction sheet body 1 for fuel is formed by adding weak magnetic energy such as a negative electron generating natural mineral and a magnetic element to the main components of SiO3 and Ce203. An incomplete combustion reduction sheet body 7 for air is formed by adding the negative electron generating natural mineral and magnetic element to the main components of SiO3 and Ce203 and by adding weak magnetic energy to fixed carbon and Fe203 and Al203. By the synergistic effect under an effective balance between these two types of sheets, the incomplete combustion is allowed to mostly near the complete combustion.