Abstract: Through the "Questionnaire on Happiness of PhD Students" sent out to and withdrew from a total of 784 PhD students majoring in Engineering, Science, Management, Law and Art in Beihang University, the actual status of these PhD students' well-being has been obtained. A range of factors existing in the motivation and reality of pursuing doctoral degree which may lead to PhD students' low level of happiness have been analyzed. Based on this investigation and years' work experience in ideological and political education of PhD students, this article has put forward several suggestions from the perspectives of ideal and beliefs, academic research, communication between students and teachers, career planning and so on to improve the level of PhD students' happiness.