PURPOSE: To produce the titled compound useful as solvent, raw material for polymer, etc., relatively safely and easily without using hazardous raw material, by reacting a specific oxirane with a specific lactone in the presence of a catalyst.

CONSTITUTION: An oxirane compound of formula I [n is 0 or 1; m is 1W3; when m is 1, R1 is H or univalent hydrocarbon residue (having 1W10C substituent group) and when m is 2 or 3, R1 is bivalent or trivalent hydrocarbon residue) having 2W20C substituent group)] (e.g. epichlorohydrin) is made to react with a lactone of formula II (R2WR5 are H or 1W10C alkyl) (e.g. β-butyrolactone) optionally in a solvent in the presence of a catalyst preferably at 50W200°C usually for 5W30hr to obtain the objective compound of formula III. The catalyst for the above reaction is preferably a quaternary ammonium salt or quaternary phosphonium salt of formula IV (A is N or P; R6WR9 are 1W10C alkyl, etc.; X- is counter ion forming an onium salt).