Informed by basic psychological needs theory, this multi-case study explored four supervisors' feedback practices and their effects on Chinese English-major students' engagement with feedback on their undergraduate dissertations written in English. Data comprised interviews with students and supervisors, stimulated recalls with students, audio recordings of supervisor-student conferences, and students' multiple dissertation drafts with supervisory feedback. Cross-case comparisons were made to gauge the supervisory support. The analyses revealed salient differences in pedagogical caring, optimal structure, and autonomy support provided by the supervisors. The supervisees engaged affectively, behaviorally, and cognitively with supervisory feedback to different extents, and their engagement depended on the types and amounts of teacher support available. The findings of the study contribute to the application of basic psychological needs theory by extending it to undergraduate dissertation supervision. Practical implications for improving undergraduate dissertation supervision in the Chinese context are proposed.