Smart phone can be a have everything that one expects to find . Therefore , many students have their own smart phone . Smart phones are indispensable for student’s dily, in this objective we would like to know the reasons of students addicted to smart phones , such as some students use the smart phone to search some information to their purpose. Also , they will play the online games or listen music in their rest . Furthermore , we can use smart phone to chat with friends and use the social websites to know the information, such as facebook, twitter, instagram, weibo etc , it is so convenient . We can find out the reasons in questionnaires.