<p>A process for producing a polyol having a high biomass proportion by causing ethylene oxide to evenly undergo ring-opening addition to castor oil or a castor oil condensate as an initiator in the presence of a catalyst and forming primary hydroxyl groups at a high efficiency while preventing the initiator from decomposing and thereby generating a low-molecular by-product. Also provided is a polyol produced by the process. The process for polyol production comprises causing one or more heterocyclic compounds to undergo ring-opening addition to at least one initiator selected among castor oil and castor oil condensates in the presence of a catalyst for cationic polymerization. It is characterized in that the heterocyclic compounds are one or more compounds selected from the group consisting of cyclic ethers and cyclic esters, at least part thereof being ethylene oxide, and that the cationic-polymerization catalyst is at least one member selected from the group consisting of aluminum compounds and boron compounds each having a fluoroaryl group or fluoroaryloxy group.</p>
