This paper explores the relationship between the student-supervisor relationship (SSR) and postgraduate students' subjective well-being. Based on a longitudinal survey of Beijing college students, the present study suggests that in China, the SSR is a supervisor-centred, top-down hierarchical relationship. The reciprocity level of the SSR is positively related to the students' subjective well-being. The trust level of the SSR also has a positive relationship with students' subjective well-being; improving the trust level may also mitigate the possible negative implications of the low level of reciprocity in the relationship. The present study further reveals that it is more difficult for first-generation students to establish sound SSR than non-first-generation students. Additionally, a good SSR is more important for first-generation students' positive well-being. The findings provide implications for educational practices on how to improve postgraduate students' subjective well-being by improving the SSR.