气候变化正通过高纬度地区的升温及热带地区的水文限制重塑全球复种潜力。在中国坚守耕地红线、稳定耕地总面积的政策背景下，提高复种指数对于在不扩大耕地面积的前提下增加粮食产量至关重要。本研究将统计降尺度气候数据整合至全球农业生态区（GAEZ）模型中，模拟了2025–2050年不同共享社会经济路径（SSPs）下中国5 km分辨率的复种潜力。结果显示，中国超过60%的耕地具有提高复种指数的潜力，热点区域集中在长江下游流域、四川盆地和黄淮海平原。其中，超过一半的区域可支持增加一季非水稻作物种植，约25%的区域可增加一季水稻种植。复种潜力呈现明显的西北至东南梯度分布，“有限三熟”是最普遍的升级类型。在高排放情景下，适宜双熟和三熟的面积扩大，而适宜单熟的面积缩小；SSP5-8.5情景下的改善峰值出现最早，SSP1-2.6情景下最晚。这些预测反映的是气候适宜性的变化，而非整体农业效益的提升。研究结果揭示了显著但空间异质性强的复种集约化潜力，为区域性农业适应提供了科学依据。

Climate change is reshaping global multiple cropping potential through warming at higher latitudes and hydrological constraints in the tropics. Under China’s red line policy to stabilize total arable land, increasing cropping intensity is crucial for raising grain output without cropland expansion. Here, statistically downscaled climate data were integrated into the Global Agro-Ecological Zones (GAEZ) model to simulate cropping intensity potential at 5 km resolution across China for 2025–2050 under different shared socioeconomic pathways (SSPs). More than 60% of China’s cropland exhibits potential for increased cropping intensity, with hotspots in the lower Yangtze River Basin, Sichuan Basin, and Huang–Huai–Hai Plain. Over half of these areas could support an additional season of nonrice crops, and approximately 25% an additional rice-growing season. Multiple cropping potential exhibits a clear northwest-to-southeast gradient, with ‘limited triple cropping’ as the most widespread upgradable type. Under higher-emission scenarios, area conductive to double- and triple- cropping expands whereas those suitable for single cropping contracts, with peak improvements occurring earliest under SSP5-8.5 and latest under SSP1-2.6. These projections represent changes in climatic suitability rather than overall agricultural benefits. These findings reveal substantial but spatially heterogeneous potential for cropping intensification and provide a scientific basis for regionally targeted agricultural adaptation.