Diary method can help user experience (UX) researchers to understand the behaviour and intention of a user in a real environment for a period of time without being present. To capture accurate and effective diary data and improve the overall quality of the diary study, the author presents a new tool for supporting diary studies. Context-awareness User Experience (CAUX) tool is able to perceive the user’s situation by using context-awareness technique in appropriate way so as to remind users of recording diary entries timely. And some techniques such as sensors can be used to collect user data which can serve as clues to help users recall, thus some comparative experiments can be designed to evaluate CAUX tool for supporting diary studies, comparing diary entries collected by this method with those collected in traditional method. The result shows that diary entries collected by CAUX tool have advantages in the numbers of words, effectiveness, accuracy, and the abundance of diary. CAUX tool can collect a higher quality of diary entries, and also provide the powerful support to help the UX researchers find more valuable insights and findings.