A fast-paced changing 21st century has raised discussions about how to best prepare youth for successful adulthood as well as building a better world. Global Citizenship Education (GCE) has been one alternative that gains widely support in the last decade as a result of globalization. Formal schooling is argued as providing the best opportunity of learning for preparing the general population of young people to become responsible and responsive global citizens in an effective and unbiased way (Print, 2015). The implementation of relevant ideas in schools calls for development in curriculum design. Among others, China has been emphasizing GCE themes in policies and exploring curriculum development aimed at developing global orientation among students. This study explores the intention and practice of GCE in the formal and informal curriculum in China’s secondary education. Utilising a multiple case study strategy, the research provides indepth descriptions of the pertinent forms of practice related to GCE in six high schools in Beijing and Shanghai. In formal curriculum, the findings show both explicit and implicit elements of GCE in the compulsory subject Political Studies. In informal curriculum, it finds an emphasis on the competence and awareness dimensions and a lack of engagement dimension of GCE in student activities within schools. Cross-case analysis finds variations in the design of GCE practice in different types of schools although within a centralised education system. The findings add to the knowledge of curriculum development regarding GCE in non-western contexts and provide empirical data of GCE from a school approach.