This mixed-methods study investigates the differences in demotivation between Chinese and Korean English teachers. A questionnaire on demotivation was conducted on 58 Chinese and 94 Korean in-service teachers to find out the dominant factors in teacher demotivation. Follow-up interviews with teachers were conducted to explore the reasons as to why teachers found the salient factors to be demotivating. The results indicated that the number of students per English classroom was the detrimental factor for both Chinese and Korean teachers. Moreover, the only factor that Chinese teachers perceived to be more demotivating than Korean teachers was the excessive interference or expectations of school parents. For Korean teachers, large amounts of administrative tasks and students' lack of interest in English were found to be the most detrimental factors. From the findings of this study, practical implications as well as research suggestions are provided.