Normal corn starch was used as raw material in this research and was treated by autoclaving method to produce corn resistant starch (CRS). This research was focused on techniques of preparing CRS through autoclaving method and effects of autoclaving method parameters on yields of CRS from corn starch. The optimum conditions were investigated with carrying out an L9(34) orthogonal experiment. The yield of CRS was 8.05 % under combination of optimum parameters obtained from L9(34) orthogonal experiment. The optimum parameters were concentration of NCS solution 25 %, pH6.5, autoclaving temperature 125 °C, autoclaving time 35 min.