Although English medium instruction (EMI) has received exponential growth of attention in recent years, the scope of research on EMI teachers is still limited, and even much less on their emotions. Drawing on an ecological perspective as the theoretical framework, we explored Iranian EMI teachers' emotion labour across the classroom, institutional and sociocultural ecologies. Data were collected from narrative frames and semi-structured interviews. Data analysis revealed three themes in relation to Iranian EMI teachers' emotion labour: (1) classroom ecology: student expectations as impeding effective content enactment, (2) institutional ecology: workload as a hurdle for investment in personal growth and (3) sociocultural ecology: low international collaborations complicating knowledge dissemination. The study shows that beyond their personal proclivities, Iranian EMI teachers face socio-educational challenges that not only complicate their pedagogical effectiveness, but also stop them from imagining the identity of global citizens within the community of EMI practitioners. We also provide implications for EMI teacher educators to draw on the study findings to run teacher education courses that tap EMI teachers' emotions.