This paper investigates how teachers' disciplinary knowledge shapes their recontextualisation practices for promoting powerful knowledge in classrooms. Situated within the context of geography education in China, this study employs a qualitative case study methodology to examine the recontextualisation of urban geography by four upper secondary school teachers with diverse academic backgrounds. Through a comprehensive analysis of teacher interviews, classroom recordings and teaching-related documents, this study uncovers and explains the variations in recontextualisation practices among the case teachers. The findings reveal that despite the dominant role of official curriculum materials, teachers maintain agency in recontextualising their disciplinary knowledge. Variations in understanding of the discipline directly influence whether, what and how much knowledge is recontextualised by teachers. Additionally, this study highlights the crucial role of teachers' motivational factors in shaping their recontextualisation practices. These factors include intrinsic motivation, characterised by a positive attitude towards and interest in disciplinary knowledge and awareness of external challenges, such as the perceived demandingness of assessments and the inadequacy of curriculum materials. Understanding these dynamics provides valuable insights for enhancing powerful-knowledge-rich curriculum making and teachers' professional knowledge.