To imporve the physical and chemial properties of polyacrylonitrile, acrylonitrile monomer was copolymerized with the various mole percentage of modifiers, N-vinylpyrrolidone, glycidylmethacrylate and N-($eta$-Hydroxyethyl) methacrylamide. The ηinh of modified polyacrylonitrile was improved in proportion to the mole percentage of modifier in the copolymer. The moisture retrain of modified polyacrylonitrile containing N-vinylpyrrolidone and N-($eta$-Hydroxyethyl) methacrylamide was rapidly increased in proportion to the mole percentage of modifier in the copolymer. In case of acrylonitrile-glycidylmethacrylate copolymer, moisture regain was slightly increased. The antistatic property of modified copolymer was favorably imporoved in comparison with that of acrylonitrile homopolymer. The tensile strength of modified polyacrylonitrile was decreased slightly. The acid dyeability of the modified polyacrylonitrile was provided with amide group by N-vinylpyrrolidone and N-($eta$-hydroxyethyl) methacrylamide was increased. In addition, the dyeability to acid dye of the acrylonitrile-glycidylmethacrlate copolymer was increased too.