Objective To analyze medical graduate students' satisfaction with advisor's guidance and its influencing factors, in order to provide empirical support for improving the satisfaction of medical graduate students with mentor guidance. Methods A questionnaire survey was used. From January to April 2022, 129 full-time medical graduate students in a top-three hospitals affiliated to Shanghai Jiao Tong University School of Medicine were selected as the survey objects by using the convenient sampling method, and a self-designed questionnaire was developed and implemented to investigate aspects of teacher-student communication, scientific research habit training, and graduation project guidance. Multiple linear regression was used to analyze the influencing factors of graduate students' satisfaction with mentor guidance. Results There were 104 graduate students (80.6%) who very satisfied with the advisor's guidance. The frequency of teacher-student academic communication (b=0.26, P=0.026), non-academic communication (b= 0.37, P=0.003), and discussion of thesis topic between teachers and students (b= 0.66, P=0.002) were significantly positively correlated with satisfaction with advisor's guidance, whereas advisor's mandatory assignment of thesis topic (b=-0.42, P=0.024) was significantly negatively correlated with satisfaction. Conclusions The satisfaction of graduate students with mentor guidance needs to be improved. Increasing the frequency of academic and nonacademic communication between teachers and students, and enhancing the frequency of thesis discussion between teachers and students are necessary to improve student satisfaction. The selection of student thesis topic should fully consider students' own interests.