The present invention relates to a damaged hair improving agent, comprising: (A) an ester compound made from dipentaerythritol and at least one fatty acid selected from the group consisting of fatty acids having 5 to 16 carbon atoms, wherein the molar ratio of dipentaerythritol residue to the fatty acid (having 5 to 16 carbon atoms) residue ranges from 1.0:3.0 to 1.0:6.0, and one or more substances selected from the group consisting of (B) an ester compound having a linear or branched alkyl or alkenyl group having 16 to 18 carbon atoms wherein hydrogen atoms on these groups are optionally replaced with hydroxyl groups, and a viscosity of 2,000 mPa·s or less at 25°C (exclusive of the component (A)), (C) an alcohol having a linear or branched alkyl or alkenyl group having 16 to 18 carbon atoms and a viscosity of 2,000 mPa·s or less at 25°C, and (D) hydrocarbon oil having at least 20 carbon atoms. The damaged hair improving agent imparts sleek fell to damaged hair and reduces gritty feel of the damaged hair to impart smooth feel to the damaged hair.
