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The object of this study was to explore the high quality and yield cultivation mode for maize in the north drought region. The impacts of different straw mulching modes in different growth stages on maize root-shoot ratio, root temporal and spatial distribution, surface biomass, yield and water use efficiency were analyzed through field contrast experiments from 2012 to 2013.There were a conventional tillage and four straw mulching modes in the experiments, which were surface tillage with straw mulching, no-tillage with straw mulching on furrow, no-tillage with stubble mulching, and no-tillage with straw mulching on ridge and furrow. SPSS statistics software was adopted to conduct significance analysis for data of jointing stage and harvesting stage respectively. The results showed that different straw mulching farming modes had significant effect on the control and support in root, root-shoot ratio and earth surface biomass, obvious effect in the early jointing stage. In addition, no-tillage with straw mulching on ridge and furrow was inferior to conventional tillage. But the other four kinds mulching models were better than comparison for 1.56%~5.48% in growth of earth surface biomass, higher than comparison for 15.10%~32.36% in root weight density, and higher than comparison CK for 10.38%~32.74% in root-shoot ratio. The yield and utilization efficiency of water were respectively higher than comparison for 10.38%~32.74% and 4.22%~12.31%. Surface tillage with straw mulching was an ideal cultivation method for cold and arid regions of North China, which had significantly advantages in growth of root formation, yield increase and water availability. 