There is provided a process for producing an organic-inorganic hybrid glassy material, including the sequential steps of (a) concentrating a starting sol of an organic-inorganic hybrid glassy material, thereby yielding a precursor material having meltability; (b) melting the precursor material; (c) subjecting a product of the step (b) to a heating treatment under reduced pressure; and (d) subjecting a product of the step (c) to a high-temperature heat treatment at 300.degree. C. or higher.