This study investigated the relationship between students' intrinsic learning motivation and mind wandering as well as the moderating role of teachers' emotional display and emotional labor strategies in class, drawing upon the attention-based view. With a sample of 1098 undergraduates, 159 teachers and 10 research assistants from a university in Beijing, China, this study found that students' intrinsic learning motivation was negatively related to their mind wandering; teachers' emotional display strengthened the relationship between students' intrinsic learning motivation and mind wandering; and surface acting weakened the moderating effect of teachers' emotional display on the relationship between students' intrinsic learning motivation and mind wandering. These findings highlight the important role of teachers' emotional display in limiting the occurrence of students' mind wandering in class. The theoretical and pedagogical implications were discussed.