There has been substantial research in the United States, Europe, and Australia about factors influencing students' well-being. However, such research has been relatively rare in Mainland China. We administered four predictor scales (School Satisfaction, Self-Concept, Relationships, and Resilience) and three outcome scales (Flourishing, Mental Health, and Children's Well-Being) to 2,756 primary and middle school students in Mainland China. Confirmatory factor analysis indicated that the measured concepts were salient to the participants. Structural equation modeling using MPlus showed that Resilience was a strong predictor of all outcome measures, particularly for Mental Health and Positive Emotional State. Global Self-Concept was the most notable predictor for Positive Outlook, whereas School Satisfaction was the strongest predictor of Flourishing. The results indicate potential areas for school-based competency-building initiatives to promote Mainland Chinese students' well-being.