It is to provide a silsesquioxane having α,β-diol group, and to provide an organic-inorganic hybrid resin composition comprising silsesquioxane and hydroxyalkyl cellulose. A composition comprising a cage-type structure of silsesquioxane represented by general formula (A), and a partially cleaved cage-type structure of silsesquioxane represented by general formula (B); (RSiO3/2)l  (A) (RSiO3/2)m(RSiO2H)n  (B) [wherein in formulae (A) and (B), l and m represent an integer of 4 or more, n represents an integer of 1 or more, and n/(l+m) is 0.03 to 0.2; each R may be the same or different, and represents an alkoxy group with 1 to 10 carbons, etc.; wherein at least one R in one molecule is a group having α,β-diol group, and when the number of groups having α,β-diol is 2 or more, they may be the same or different].