Mentor system is one of the basic systems of Yuanpei Program. It is an important guarantee for Yuanpei students to choose majors according to their own interests and abilities, and to select courses independently and rationally. The basic work of mentors involves several aspects, including major selection, university life adaptation, academic research guidance, and professional development.

School-appointed mentors: After more than ten years of efforts, Yuanpei College has established a team of school-appointed mentors covering all departments of the school. All the mentor appointment is issued by the then-President, and the length of each term is 3 to 4 years. The mentors will guide the freshmen to adapt to the study and life in Peking University. They also provide valuable guidance and necessary consultation for students in the study of core subjects and liberal arts courses, and in the choice of major. For Yuanpei students who have chosen their majors, mentors assist them in communication with relevant departments (e.g. the arrangement of extra-classroom teaching activities such as second classroom mentoring and teaching practice, etc.). Mentors also carry out students' liberal arts education and fieldwork education in various ways, helping them in their academic practice, thesis writing, scientific research preparation and so on.

Professional mentors: Yuanpei College is trying to establish a team of professional mentors from various departments to participate in the formulation and adjustment of corresponding program courses . They can provide direct guidance in scientific research for students, along with internships. Teaching by percept and example, professional mentors improve students' professional interest, cultivate their research awareness and scientific spirit, and offer them standardized scientific training.

Full-time mentors: Full-time mentors are served by retired professors. They take turns on duty by week and work in Yuanpei Student Dormitory to facilitate close communication with students. They guide students in their study, life, thoughts, emotion, and dormitory interpersonal relationships. They help resolve their confusion and provide timely psychological counseling.