This research focuses on enhancing teacher mediation to foster students’ metacognition in flipped learning classrooms in a middle-high school in China. A series of designed workshops aimed to develop teachers’ professional understanding of metacognitive engagement in flipped learning classrooms and facilitate their exploration of classroom talk with a view to enhancing students’ metacognitive thinking to assist their learning. Flipped learning, as one example of digital learning, is increasingly pervasive in many educational settings. Research suggests that self-regulated learners benefit more in the flipped learning pedagogical environment than those who have low self-knowledge and self-management. Self-regulation is one of the main subcomponents of metacognition. There is a need to help teachers to be metacognitive teachers, so that in turn, metacognitive learners may be cultivated through daily classroom instructional activities and teacher practice. The school in this study had identified a need to further develop metacognition in their flipped classroom learners. The study used an interpretive methodology and a qualitative research approach to explore the use of dialogic talk processes by teachers to engage in metacognitive thinking with their students within the flipped learning context. Data were gathered through classroom observations prior to and after a series of designed professional learning workshops for the teachers. Key incidents of teachers using dialogic talk were captured by video during further classroom observations and post-observation interviews with teachers, and student focus groups and analysis of student work completed the dataset. The participants in this study included five teachers and their students, to investigate the phenomena of teacher mediation in students’ development of cognition and metacognition in a flipped learning approach. In this study, the use of flipped learning suggested a need for metacognitive learners and metacognitive teachers. I worked with teachers to develop their own and their students’ metacognitive thinking. The reflective practice process of teachers was an aspect of the professional learning workshops, which provided me with teacher input into a theoretical framework, which resulted in an extended and detailed dialogic talk process, generated to guide teachers in designing their instructional activities and further applications in their classroom practice. The classroom practices of one English, one Maths and one Chemistry teacher were used to exemplify how the professional learning about mediating metacognitive development could be put into practice. The study attempted to highlight the complexities of dialogue that shape learners’ sense making and influence future effective pedagogical practices. At the final stage of the research, through teachers’ and students’ reflections on metacognitive teaching and learning, classroom atmosphere, power, talk and nonverbal behaviours were identified as the factors that influence the engagement of metacognitive teaching and learning in flipped learning. This study has furthered the understanding of the nature of teachers’ mediation and the practices of teachers and students in mutually engaged dialogic talk concerning the development of metacognition within a school-wide flipped learning adoption context. The design and outcomes of this research may help teachers create an interactive environment in both online and offline learning, incorporating metacognition instructions to facilitate students’ ability to become increasingly autonomous and self-regulated in their learning.