This article examines how teachers' social-media based relationship with parents shapes the way they feel about themselves as a teacher. Based on 11 Chinese teachers' experience of using WeChat (the dominant social media application in China) in their relationship with parents, the analysis shows that social media enable teachers to have prolonged and direct interaction with parents and have therefore become an important arena for their identity construction. Working with parents through social media has led to their sense of self as a teacher being continuously enhanced, enriched, or transformed. The findings suggest that three different modes of identity work, i.e., affirmation, integration and exploration, were performed by teachers in their social-media-based relationship with parents.