To date, there is a paucity of research on graduate students' learning experiences in teacher education, and we also know little about what support they might need in their learning to become teacher educators. In order to fill this gap, this study draws on three graduate students' experiences, to explore how a PhD programme in a university in China seeks to develop prospective teacher educators, which can generate useful implications about the effective preparation of teacher educators in higher education. One central question guides this study: "how did the three PhD students learn to become teacher educators in their programme?" This study demonstrates that the PhD programme largely contributed to the participants' professional growth as language teacher educators in three important ways. First, the programme provided rich opportunities for the participants to engage in teaching of both pre- and in-service teachers with scaffolding and guidance. Through their teaching, they integrated the theories they acquired from the coursework with real practice, developed a repertoire of teaching skills and strategies and enhanced their personal practical knowledge of teacher education. Second, the programme created a critical platform for the participants to engage in collaboration with school teachers and teacher educators in research projects, which served as another powerful source for their learning. Third, the programme also encouraged the participants to explore critical issues in current language teaching and teacher education through their PhD research (though they were free to choose their individual research topics), with a view to promoting their research abilities and knowledge base as teacher educators/researchers.