Hydrogen energy infrastructure is expected to be a key technology for developing a sustainable society. However, the production route of hydrogen is still an important open problem. One prospective route of hydrogen production is a solar hydrogen system. In such a system, the thermal radiation spectrum, which plays an important role in chemical reactions, can be controlled by applying a two-dimensional surface grating to radiative materials. We used spectrally controlled thermal radiation to promote methane-steam reforming. Therefore, we demonstrated that hydrogen production strongly depends on the spectral intensity within the particularly resonant wavelength range, and that the amount of hydrogen produced is 5.8 times greater than that using normal thermal radiation. The conceptual design of a solar hydrogen system using spectrally controlled radiation is presented.