Background/Introduction Based on the Job Demands-Resources model, this study examines how six dimensions of the working environment shape teacher occupational well-being (TOWB) in the context of high-stakes primary education systems. Methods Drawing on a 2020 national survey of 25,028 Chinese primary school teachers, the study employed CEM and SEM to analyze the data and provide convergent evidence for causal inferences. Results Findings reveal a moderate TOWB level with significant demographic variations. The six-dimensional working environment explains 71.6% of the variance in TOWB. Specifically, professional development and policy support are the strongest positive predictors, whereas workload exerts a robust negative impact. Furthermore, school culture partially mediates the relationship between the environment and TOWB. Discussion The results highlight the necessity of workload audits, tailored professional development, and faithful policy implementation. This study offers contextual, methodological, and conceptual extensions of JD-R theory within the primary education sector.