An alignment layer composition including a copolymer of a dianhydride compound and a diamine compound, wherein the copolymer includes a repeating unit represented by Formula 1: wherein each of Ar1 and Ar2 is independently a substituted or unsubstituted aromatic group comprising 6 to 30 carbon atoms, X is an electron donating group, and is an ester group, wherein “*” indicates a point of attachment to the aromatic groups Ar1 and Ar2.