An alkali metal compound such as metallic cesium, cesium hydroxide, cesium hydroxide monohydrate, metallic rubidium, rubidium hydroxide or rubidium hydroxide monohydrate is used as a catalyst, crude polyoxyalkylene polyol containing the catalyst is neutralized with a mineral acid or an organic acid, an aqueous solution layer containing an alkali metal salt is brought into contact with an anion exchange resin to adsorb mineral acid anion or organic acid anion, the alkali metal compound catalyst is recovered. alkylene oxide undergoes ring-opening addition polymerization on an active hydrogen compound in the presence of the recovered alkali metal compound catalyst to prepare polyoxyalkylene polyol, the catalyst is thereafter separated, recovered and reused, and such recycle of the alkali metal compound catalyst provides an economical process.