<p>The rise of positive psychology (PP) has inspired educators in different fields to move toward positivity and emotionality. An emerging venue for PP has been second/foreign language (L2) education given its emotional essence. While many studies are exploring various aspects of PP in English as a foreign language (EFL) contexts, they are mostly correlational. Nevertheless, teachers’ perceptions and experiences of PP use in EFL classes have remained under-explored. To fill this gap, this study aimed to examine Chinese EFL teachers’ perceptions about the use, benefits, setbacks, and requirements of applying PP in L2 education. To this end, a sample of 21 Chinese EFL teachers with various educational and pedagogical profiles attended a semi-structured interview. The findings indicated that Chinese EFL teachers perceived various benefits for PP use including its capacity to generate positive emotions, stop and reduce negative emotions, improve professional expertise and feelings, establish positive, friendly, and interactive learning environments, and strengthen one’s character. Concerning challenges, it was found that PP application had been tough in China because of its logistic demands, teacher-related and learner-related factors (e.g., personality, needs, and openness to diversity/change), polices and rules, and the need for training. Moreover, the findings showed that PP use requires positive classroom climates, attitudes, and relationships, along with special training, emotional literacy, individualized instruction, school support and resources, and a humanistic teaching style. The study discusses the findings and implications for EFL teachers and educators, who can realize the benefits, challenges, and requirements of PP use in L2 classes.</p>