In order to develop modified starch using reinforced corrugating medium, this study carried out to decrease reaction time and simplify process cyanoethylation of starch after acid treatment of native corn starch. Native corn straches(81g oven dried) were reacted with 150mL of 5% aqueous hydrochloric acid at 40℃ for 30minutes. Acid treated starches(ATS) were cyanoethylated to the 0.1 to 0.4 ratios AN/ATS under alkali condition(pH 12) at 40℃. The degree of substitution(DS) of cyanoethylated starches was 0.003∼0.019 with reaction times(30, 60 and 120 minutes). The preparation of handsheets has been with 1%, 2% and 3% of CES add levels with DS, respectively. The strength properties of handsheets added CES showed a tendency to increase in comparison with untreated handsheet, especially, the compression strength(ring crush) of handsheets was highest in 3% add level of DS 0.003 CES.