Drawing upon a collection of curriculum proposals and reflections and informed by a textual analysis approach, this study investigated how 234 university teachers planned to enact and reform their English-medium instruction courses (n = 66) in an English as a foreign language (EFL) university context. Results reveal that the teachers tend to adopt a student-centered teaching approach with a focus on content learning. Teacher collaboration and technology use were two facilitative factors for EMI curriculum operation in different disciplines. In addition, the teachers attempted to evaluate and reform their courses through multiple paths including internet survey, material analysis, and classroom-based research. On the other hand, the study also identifies some challenges encountered by the teachers in their EMI curriculum development, namely, a lack of language awareness, limited cross-disciplinary collaboration, and relatively low level of professional development. Based on the research findings, practical implications are provided to enhance EMI teaching and teacher education in EFL tertiary institutions.