Syntheses and polycondensations of optically active hydroxycarboxylic acids prepared from acid anhydrides and aminoalcohols were carried out. Novel polymers with (M) over bar(n) 9900-27,200 were obtained by the polycondensations of hydroxycaboxylic acids derived from maleic or succinic acid using 1.2 eq. of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC . HCl) in DMF (2M) at room temperature for 8 h in satisfactory yields. Meanwhile, a hydroxycarboxylic acid obtained from phthalic acid afforded no polymer but a phthalimide derivative. The radical additions of ethanethiol or mercaptoethanol with the polymers derived from maleic anhydride proceeded smoothly in satisfactory incorporation ratios (65-98%), respectively. The polymer obtained from succinic anhydride and 2-aminoethanol showed hydrolytic degradability.