This study reports on a longitudinal inquiry into professional identity construction among six novice cross-border English language teachers from mainland China, who completed their pre-service teacher education in Hong Kong (HK) and began their teaching practice in local HK schools. The findings indicate that the participants navigated obstacles in teaching by deploying their own multiple languages as a cultural and linguistic repertoire. The findings also show that the teachers experienced difficulty legitimising their professional identity in the teaching community, where contextual issues and power interplays mediated the process. Furthermore, it is found that the participants' commitment to teaching was negatively influenced by their non-legitimate position in the teaching community and the discordance between their teaching beliefs and the norms and values of their workplace. This study suggests that complex inter-relationships between marginal status in and legitimate membership of the community, between historical and cultural background, present practice, and future expectations, between social discourse and personal location, are involved in the process of identity construction. Measures to legitimate these teachers' position and to transform the linguistic and cultural repertories of these teachers into valuable resources of the local schools are suggested. Implications for future research are outlined.