The reform of English for academic purposes (EAP) teaching requires clear understanding of its conceptual connotation. Based on the legitimation code theory, this study analysed the development of EAP in major English-speaking countries and the debates on the concept of EAP in the academic community. The study finds that EAP has evolved from a knowledge code, a knower code to an elite code. The core elements of EAP are embodied in a hierarchical knowledge structure, a systematic curriculum framework, and the integration of knowledge and knower in teaching. Therefore, in response to the current debates and problems in China’s EAP teaching and research, it is suggested that EAP teaching should focus on the dialectical unity of language knowledge and disciplinary knowledge, academic skills and academic literacies, knowledge creation and personal development, so as to achieve the resonance of talent cultivation and national development. This article was published open access under a CC BY-NC-ND licence: https://creativecommons.org/licenses/by-nc-nd/4.0/ .