Hydrogen peroxide has attracted increasing interest as an environmentally benign and green oxidant that can also be used as a solar fuel in fuel cells. This review focuses on recent progress in production of hydrogen peroxide by solar-light-driven oxidation of water by dioxygen and its usage as a green oxidant and fuel. The photocatalytic production of hydrogen peroxide is made possible by combining the 2e⁻ and 4e⁻ oxidation of water with the 2e⁻ reduction of dioxygen using solar energy. The catalytic control of the selectivity of the 2e⁻ vs. 4e⁻ oxidation of water is discussed together with the selectivity of the 2e⁻ vs. 4e⁻ reduction of dioxygen. The combination of the photocatalytic 2e⁻ oxidation of water and the 2e⁻ reduction of dioxygen provides the best efficiency because both processes afford hydrogen peroxide. The solar-light-driven hydrogen peroxide production by oxidation of water and by reduction of dioxygen is combined with the catalytic oxidation of substrates with hydrogen peroxides, in which dioxygen is used as the greenest oxidant.