<p>Despite the widespread adoption of English as a Medium of Instruction (EMI) in Chinese universities, low levels of student engagement in classroom are a persistent issue. As a practical theory of language, translanguaging provides a new perspective for EMI teaching. While the study of translanguaging practices in the second/foreign language classroom has been relatively systematic, the influence of translanguaging pedagogies on student engagement in the context of Chinese universities remains under-researched. By employing a sequential explanatory mixed-methods design, this study investigated the impact of translanguaging on student engagement within EMI courses vis-à-vis monolingual instruction. Data were collected through 203 questionnaires completed by students, classroom observations during instruction, and follow-up interviews with students. Questionnaire results showed a positive association between translanguaging and student engagement compared to monolingual classrooms. Classroom observations demonstrated the varied employment of translanguaging strategies by teachers, whereas interviews revealed that students expressed a continuum of attitudes towards these practices: English major students tended to hold negative attitudes while non-English major students showed more positive ones. Grounded in the conceptualization of translanguaging as ideology, pedagogy, and theory, the study provided implications for educational institutions, frontline teachers, and future researchers.</p>