A photoresist composition comprising: a first polymer comprising a first repeating unit comprising a hydroxy-aryl group and a second repeating unit comprising an acid-labile group; a second polymer comprising a first repeating unit comprising an acid-labile group, a second repeating unit comprising a lactone group, and a third repeating unit comprising a base-soluble group, wherein the base-soluble group has a pKa of less than or equal to 12, and wherein the base-soluble group does not comprise a hydroxy-substituted aryl group; a photoacid generator; and a solvent, wherein the first polymer and the second polymer are different from each other.