Abstract: A series of sulfonic-2-hydroxypropane corn starch (SHPS) as acidconverted cornstarch were prepared by a reaction of corn starch with an etherifying agent, 3-chloro-2-hydroxypropanesulfonic acid sodium salt.The surface morphology of SHPS granules was observed by scanning electron microscope, and the effect of sulfonic-2-hydroxypropane modification on properties of SHPS/polyacrylate composite films was investigated. Moreover, the effect of modification reaction degree on the properties of the composite films was also evaluated. The results indicated that the modification reaction improved the elongation at break of the composite films butreduced their tensile strengths, and a toughening effect was observed. In addition, thesulfonic-2-hydroxypropane modification not only enhanced the adhesion strengths of the composite films to cotton and polyester roving but also improved their degree of swelling. With the increase of modification level, the composite films achieved an increase in elongation at break by 29 % but presented a slight decrease in tensile strength. This indicates a gradual increase in toughening effect. Moreover, the adhesion strengths also increased gradually with an increase in modificationlevel.