Thailand is one of the largest rice producing countries and the local people commonly use processed rice flour for cooking. My research investigates how to increase the content of indigestible resistant starch, without altering the quality of the rice. Indigestible resistant starch has a similar function to that of dietary fibers', and it can control blood glucose level and energy intake. In the recent years, low GI foods have been gaining popularity in Japan. Therefore, increasing the content of indigesitible resistant starch would raise the demand and value of Thai rice.