The paper explores the issue of teachers' professional vulnerability using a range of messages from an online teachers' community on the Chinese mainland. The study reveals how macro changes at policy level impact on teachers' professional relationships and in turn their professional identities in teacher discussants' perceptions. Furthermore, the paper argues that the Chinese cultural tradition somehow adds to teachers' professional vulnerability. While the tradition used to give teachers authority, it imposes burdens on teachers and subjects them to close scrutiny, which consequently make them feel more vulnerable. The paper concludes with critical reflections on its methodology and findings, calling for further research into the issue.