BACKGROUND: Plastic mulching film (PMF) is extensively applied in cotton cultivation to enhance yields, yet its comprehensive environmental consequences remain inadequately quantified. OBJECTIVE: This study aims to quantify the multi-dimensional impacts of PMF on cotton production across 18 Chinese provinces by developing a yield-biomass-water-environment (YBWE) nexus analysis model. METHODS: Integrating the WOFOST crop model, mixed regression, and life cycle assessment (LCA), we evaluated effects across 35 cross-cutting promotion scenarios, accounting for provincial disparities in natural conditions and agricultural practices. RESULTS AND DISCUSSION: PMF promotion is projected to increase China's average cotton yield from 2.41 t/ha to 3.21 t/ha by 2050, with the most significant gains in the northwest inland region. While improving water use efficiency, PMF exacerbates water scarcity in arid areas, increasing consumption by 564.93 t/ha in the northwest. A "V-shaped" PMF residue belt will form, raising aggregate environmental impacts by 74.74 % compared to 2021. Economically, PMF boosts profits-especially in the northwest (up to USD 1890.61/ha)-but over 50 % of provinces face net ecological losses. The optimal scenario couples high-intensity PMF promotion in low-income regions with high-strength PMF application, reducing environmental impacts by over 40 % and avoiding USD 1.83 trillion in ecological costs. SIGNIFICANCE: This study provides a scientifically supported strategy for PMF promotion that balances yield growth with environmental sustainability, informing policy for coordinated agricultural and ecological development.