This study took the graduation thesis of the undergraduates majoring in social work in China in 2020 as the analysis object, sorted out and analyzed the research methods used in the thesis and the problems encountered through the questionnaire survey. Research findings: the research topic of graduation thesis will affect the choice of research methods. The research methods used are diversified, mainly mixed research. In the mixed study, the research method is mainly qualitative, while in the qualitative study, the specific research method is in mcdonaldization. Quantitative research is mainly based on investigation, and the level of quantitative data analysis is relatively low. The thesis writing dilemma mainly focuses on the use of data collection and analysis methods. Through analysis, the researchers on the degree of master the research methods and related experience will affect the use of research methods in the thesis, then the quality of the graduation thesis, so we should perfect the system of social research methods course, complete the research design and thesis writing instruction work, increase the chances of students practice, research and writing experience, to lay a solid foundation for my thesis writing.