The purpose of this study is to investigate any differences existing in pedagogic behaviours between Chinese teachers (CTs) and non-Chinese teachers (NCTs) in and outside the English and Science (English-medium) classrooms in an International Baccalaureate (IB) context in mainland China. It also explored potential cultural influences, students' perspectives and issues arising from any differences in pedagogic behaviours. It provided an in-depth and systematic interpretation of the reasons that cause the differences with the aim of contribution to an amelioration of the co-constructed pedagogy.