Context: Conservation agriculture, which aims to improve soil health and optimize resource-use efficiency, is a key strategy for developing environmentally sustainable systems. Research question: To comprehensively assess for the first time, the effects of different tillage practices on water utilization and crop productivity in the drylands of northern China. Methods: The effect of conservation agriculture on key crop growth parameters and water use in rainfed agricultural regions of northern China was evaluated using a meta-analysis of 12 different tillage practices. The potential long-term effects of future climate change were also assessed. Results: Based on 405 published studies, conservation agriculture significantly increased crop yield (19.94%) and water use efficiency (WUE) (19.48%) across northern China, although the effects varied by region. Mulching and ridge tillage were the most effective practices in Northwest China and the North China Plain, primarily by increasing soil water storage, leaf area index, and soil water content. In contrast, in Northeast China, deep plowing and straw return improved soil permeability and provided significant ecological benefits. When integrating environmental factors, crop yield and WUE increased the most under an optimal mean annual precipitation of 400-800 mm, mean annual temperature of 5-10 degrees C, and soil organic carbon levels of 5-10 g kg(-1). Spatial modeling further indicated that, under future climate scenarios, conservation agriculture is likely to sustain yield gains for maize and wheat across northern China, whereas the responses of other crops are more spatially variable and may turn negative in some provinces. Conclusions: Conservation agriculture enhanced WUE and crop yield across rainfed northern China, and regional variation was greatest in the Northwest, with moderate responses in the North China Plain and Northeast. Significance: These findings highlight the importance of region-specific conservation agriculture strategies tailored to local climate and soil conditions and provide insights into the potential benefits of conservation agriculture for optimizing crop production and resource use under future climate change.