To obtain a refrigerator oil improved in lubricity and in compatibility with a fluoroalkane substituting for a chlorofluorocarbon having problems with environmental pollution by compounding a base oil mainly comprising a specific polyether compd. with a phosphoric ester.

A refrigerator oil which has improved resistances to abrasion and seizure, is prevented from the degradation in external appearance and from the decrease in high-temp. critical solution temp., and has an enhanced lubricity is obtd. by compounding a base oil mainly comprising at least one polyether compd. represented by formula I and/or formula II [wherein R1 to R5 are each a 1-3C alkyl, pref. all of them are methyl; and A1 to A3 are each a polymer chain comprising 3-100 units derived from at least one kind of 2-4C alkylene oxide] with 0.1-5wt.% (based on the refrigerator oil) phosphoric ester represented by formula III [wherein R6 is H or a 1-3C alkyl; and (k) is 1 or 2 provided the sum of the numbers of carbon atoms of (R6)k is 3 or lower] (e.g. tricresyl phosphate) and necessary amts. of additives such as a load-carrying additive, a chlorine scavenger, an antioxidant, and a metal deactivator.