The manufacturing method and the hydrogen production method of the composite composition for hydrogen-producing

One composite composition according to the present invention includes: silicon fine particles; and a silicon sub-oxide (SiOX， where x in the formula is 1/2， 1， or 3/2) and/or a mixed composition of the silicon sub-oxide and silicon dioxide， at least partially covering the surfaces of the silicon fine particles. One composite composition according to the present invention includes: silicon fine particles; and a silicon sub-oxide (SiO X， where x in the formula is 1/2， 1， or 3/2) and/or a mixed composition of the silicon sub-oxide and silicon dioxide， at least partially covering the surfaces of the silicon fine particles.