Understanding the identity of non-English language teachers in Chinese secondary schools is crucial for the early cultivation of multilingual talents. This paper adopts a qualitative case study method to explore the construction and transformation of identity among six secondary school French teachers during their professional development. The study finds that the absence of French teacher training has led to a diversification of pathways into the profession. The status of French as a secondary school subject explains the co-existing identities and professional development challenges faced by French teachers. The teachers’ agency determines the extent to which their identity crises can be resolved. This paper provides targeted perspectives and research methods for the study of multilingual teacher development and offers insights for French teacher training.