Use of a grease composition for preventing white layer flaking of rolling bearings, wherein said grease composition comprises a base oil, a thickener, and an anti-flaking additive represented by formula: R 1 - S x - A wherein R 1 is a hydrogen atom, a straight-chain or branched alkyl or alkenyl group having 1 to 20 carbon atoms, or an aromatic hydrocarbon group having 6 to 26 carbon atoms; A is a hydrogen atom, -S y -R 2, -S y -B-R 3, -R 2 SH or a group represented by formula or: wherein R 2 is a straight-chain or branched alkyl or alkenyl group having 1 to 20 carbon atoms, or an aromatic hydrocarbon group having 6 to 26 carbon atoms; R 5 is a straight-chain or branched alkyl or alkenyl group having 1 to 20 carbon atoms, or an aromatic hydrocarbon group having 6 to 26 carbon atoms; B is a 5-membered heterocyclic ring having at least one heteroatom selected from the group consisting of sulfur atom, nitrogen atom and oxygen atom; R 3 is a hydrogen atom, -S z -R 4, -SH, a straight-chain or branched alkyl or alkenyl group having 1 to 20 carbon atoms, or an aromatic hydrocarbon group having 6 to 26 carbon atoms; R 4 is a straight-chain or branched alkyl or alkenyl group having 1 to 20 carbon atoms, or an aromatic hydrocarbon group having 6 to 26 carbon atoms; x is a number from 1 to 10; y is a number from 0 to 10; z is a number from 1 to 10; and w is a number from 1 to 10; where the straight-chain or branched alkyl or alkenyl group having 1 to 20 carbon atoms may optionally comprise one or more heteroatoms selected from the group consisting of nitrogen atom and oxygen atom, and/or may be optionally substituted by one or more aromatic hydrocarbon groups having 6 to 26 carbon atoms; provided that R 1 and A do not represent a hydrogen atom at the same time, wherein the anti-flaking additive is selected from the group consisting of a 2,5-dimercapto-1,3,4-thiadiazole derivative represented by formula: wherein R 1 and R 4 are each a straight-chain or branched alkyl or alkenyl group having 1 to 20 carbon atoms; sulfurized fat and oil; and olefin sulfide, wherein the anti-flaking additive is contained in an amount of 0.1 to 20 mass% based on the total mass of the grease composition, wherein the thickener is a diurea compound represented by formula: RI-NHCONH-R2-NHCONH-R3 wherein R2 is a bivalent aromatic hydrocarbon group having 6 to 15 carbon atoms; and R1 represents a straight-chain or branched alkyl group having 8 to 22 carbon atoms, or cyclohexyl group; and R3 represents a straight-chain or branched alkyl group having 8 to 22 carbon atoms, or an aromatic hydrocarbon group having 6 to 12 carbon atoms. wherein R 2 is a straight-chain or branched alkyl or alkenyl group having 1 to 20 carbon atoms, or an aromatic hydrocarbon group having 6 to 26 carbon atoms; R 5 is a straight-chain or branched alkyl or alkenyl group having 1 to 20 carbon atoms, or an aromatic hydrocarbon group having 6 to 26 carbon atoms; B is a 5-membered heterocyclic ring having at least one heteroatom selected from the group consisting of sulfur atom, nitrogen atom and oxygen atom; R 3 is a hydrogen atom, -S z -R 4, -SH, a straight-chain or branched alkyl or alkenyl group having 1 to 20 carbon atoms, or an aromatic hydrocarbon group having 6 to 26 carbon atoms; R 4 is a straight-chain or branched alkyl or alkenyl group having 1 to 20 carbon atoms, or an aromatic hydrocarbon group having 6 to 26 carbon atoms; x is a number from 1 to 10; y is a number from 0 to 10; z is a number from 1 to 10; and w is a number from 1 to 10; wherein R 1 and R 4 are each a straight-chain or branched alkyl or alkenyl group having 1 to 20 carbon atoms; sulfurized fat and oil; and olefin sulfide, wherein the anti-flaking additive is contained in an amount of 0.1 to 20 mass% based on the total mass of the grease composition, wherein the thickener is a diurea compound represented by formula: RI-NHCONH-R2-NHCONH-R3 wherein R2 is a bivalent aromatic hydrocarbon group having 6 to 15 carbon atoms; and R1 represents a straight-chain or branched alkyl group having 8 to 22 carbon atoms, or cyclohexyl group; and R3 represents a straight-chain or branched alkyl group having 8 to 22 carbon atoms, or an aromatic hydrocarbon group having 6 to 12 carbon atoms.