A polyurethane foam is obtained by reacting, foaming, and curing raw material that includes a polyol, a polyisocyanate, a blowing agent, a catalyst, and an inorganic compound hydrate. The raw material includes, as the polyol, a polymeric polyol obtained by graft polymerization of a vinyl monomer onto a polyether polyol and a polyether polyol obtained by addition polymerization of an alkylene oxide to a polyhydric alcohol and having a mass average molecular weight of 400 to 1,000. The blending quantity of the inorganic compound hydrate is 10 to 80 parts by mass per 100 parts by mass of the polyol. Preferably, the raw material further includes, as the polyol, a polyether polyol obtained by addition polymerization of an alkylene oxide to a polyhydric alcohol and has a molecular weight of 2,000 to 4,000.