The research about the development of Whole Grain cookie product aims to study about the amount of oat power that can be used instead of wheat flour in Whole Grain cookie product in order to study about the nutrition of the cookie product from oat power and the acceptance of the customer about the Whole Grain cookie product by having 40 testers which are students in faculty of technology home economics Rajamangala University of Technology Phra Nakhon. There are 5- ponit hedonic scale questionnaire. The comparison of the average uses Duncan’s New Multiple Range Test (DMRT) The tasting result found that the amount of oat power that has been used instead of wheat flour 100 percent has the most acceptances. When study about the nutrition of the Whole Grain cookie products from oat powder found that it found that they provide 68.64 Kcal carbohydrate 5.20 grams protein 1.48 grams and fats 5.33 grams. Then study more about the acceptance of Whole Grain products from oat powder. It found that the customers were satisfied with Whole Grain product from oat powder at good level and the customers accept the products from oat powder about 97.5 percent.