After studying and gathering the information about the influent factor on choosing a travel agency from the English major students the Faculty of Humanities and Social Sciences at Burapha University. The result in part 3 of our project is related to the marketing mix 4Ps. We use the marketing mix 4Ps to classify the factor into 4 parts. The result in part 4 that answers the research question number 2 in our project is related to the Generic Consumer Decision-making model "Post Purchase Behavior". The result from part 4 shows the customer's behavior after using the travel agency's service and shows the customer's satisfaction after using the travel agency, so the result is related tothe theory.