Background and Aim: The flipped classroom redefines psychological health education by using technology for independent study before class and engaging in interactive and applied learning activities in class. Thus, two research objectives were proposed: (1) To compare the difference in the effectiveness of the new MOOC-based flipped learning on students' learning outcomes compared to traditional teaching in undergraduates’ mental health curriculum. (2) To explore students' attitudes to new MOOC-based flipped teaching methods. Materials and Methods: This study was designed as a pretest and posttest trial. The sample was 60 freshmen from two Sichuan University classes allocated to two groups using purposive samplings: group 1 for traditional learning, and group 2 for flipped learning. The performance test and semi-structured interview were employed in this study as research instruments. Both groups' pretest and posttest scores were obtained for learning outcome comparison. The students' attitudes to the new teaching methods were obtained through semi-structured interviews. Results: The mean pretest and posttest scores in group 1 were 58.87 and 82.17 respectively, while in group 2, they were 58.67 and 86.53 respectively. The mean improvement in knowledge score was significantly higher in group 2 (M=27.87, SD=3.14) compared to group 1 (M=23.30, SD=1.69). The level of statistical significance was P < .001. The results of the semi-structured interviews indicated that almost all participants had very positive opinions regarding flipped learning based on MOOCs. Conclusion: The research demonstrates that MOOC-based flipped learning increases the student learning effectiveness to obtain better score performance and make it worth promoting.