Agricultural crop trade alleviates China’s water shortage but redistributes water value unevenly

China’s limited freshwater endowment tightly links water security to domestic and international crop trade. Here we develop a high‑resolution framework that couples a 1‑km grid–based crop‑water model with interprovincial and global trade matrices to quantify how trade reshapes blue (irrigation) and green (rainfall) water consumption, regional water scarcity, and the economic value of water across China. Comparing counterfactual no-trade with observed-trade scenarios for 2000, 2010, and 2014, we demonstrate that trade alleviates national water stress by reallocating production to more humid, more efficient locations and by importing water-intensive commodities. However, increases in water productivity and trade volumes mask acute disparities: wealthy coastal provinces externalize water use and experience reduced scarcity, whereas arid inland exporters face heightened water scarcity and export water at relatively high value per cubic meter. The blue-water value gains accrue disproportionately to higher-income regions in parts of western China; conversely, green-water value becomes more equitably distributed over time, narrowing East–West gaps. Although fewer people remain in moderate or severe scarcity classes overall, the burdens concentrate in exporting provinces. Our findings underscore a tension between efficiency and equity in virtual‑water trade and point to water‑aware trade policies—such as compensating water‑scarce exporters and incentivizing water‑efficient crop portfolios—to reconcile national water savings with fair regional outcomes.