University students are a key source of volunteers, and their volunteering reasons are an academic concern. Adopting a push-pull perspective, this study explores why China's university students participated in long-term volunteer teaching in distant, unfamiliar locations. Data were drawn mainly from documents and interviews with 20 university students participating in year-long volunteer teaching in distant schools. Findings reveal that students' participation resulted from the interplay of push factors causing them to leave (e.g., helping others) and pull factors (e.g., destinations and projects) enticing them to come. The interplay was exhibited in two patterns: pull factors triggering the emergence of push factors, and the former being used to realise the latter. Such interplay was facilitated by the volunteering organisation's mission, resources, and efforts to make its projects attractive. The study reflects that volunteering organisation and management in higher education institutions need to rethink how to gear their volunteering missions to suit students' diverse motivations and develop their organisational features and resources to attract and retain volunteers.