Objective: To explore the facilitating and hindering factors of mental health promotion activities in junior and senior high schools from teachers perspectives, as well as coping strategies, so as to provide evidence for implementing teacher led mental health promotion programs. Methods: From September 2023 to September 2024, by using purposive sampling method, 5 junior high schools, 5 regular high schools, 2 vocational high schools in four provinces and municipalities (Tianjin, Shanxi, Shandong, and Jiangxi) were selected. A total of 92 teachers (78 homeroom teachers and 14 full time or part time psychological counselors) were interviewed using semi structured focus group discussions (one session per school, totaling 12 sessions). Thematic analysis was applied to code and analyze the interview transcripts. Results: The implementation of mental health promotion activities in middle schools was influenced by three levels: teachers, schools and society. Specifically, teachers exhibited a high support low capability phenomenon (81 participants supported conducting such activities, but 71 felt lacking in professional capacity); activity effectiveness and support systems were imbalanced (42 mentioned significant effects, while 78 reported insufficient support); there was a mismatch between student demand and activity content (9 mentioned students had psychological needs, but 11 indicated existing activities failed to meet these needs); administrative support and sustainability showed disparities (14 believed sufficient administrative support existed, while 37 noted sustainability issues); parental awareness and participation remained inadequate (11 highlighted parents need for mental health knowledge, and 37 perceived insufficient understanding of psychological issues among parents). Effective strategies included enhancing teachers effectiveness, providing essential skill training, focusing on the needs of teenagers,enhancing program sustainability, and eliminating misconceptions about mental health among parents. Conclusion Mental health promotion activities in junior and senior high schools should focus on enhancing teachers skills, improving activity sustainability, reducing stigma among parents, and establishing a collaborative network for school based mental health promotion.