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A field experiment was conducted to investigate the effect of varying supply methods of nitrogen and irrigation on dynamics and distribution of soil nitrate nitrogen during maize (Zay mays L., cv. Gold northwestern 22) growth in Northwest China. Irrigation methods included alternate furrow irrigation (AI), fixed furrow irrigation (FI) and conventional furrow irrigation (CI). Nitrogen supply methods included alternate nitrogen supply (AN), fixed nitrogen supply (FN) and conventional nitrogen supply (CN), which were applied at each irrigation. Maize rows were established in west-east direction. Soil nitrate nitrogen content in south and north of the plant was measured in 0~100cm soil depth (20cm as an interval) before planting and at 6 collars, 12 collars, tasseling, filling and maturity stages. The results showed that spatial-temporal distribution of soil nitrate nitrogen in south and north of the plant was influenced more by varying methods of nitrogen supply and irrigation compared with that under the plant, so did that in 0~40cm soil depth compared with that in 40~100cm. At filling stage, soil nitrate nitrogen of irrigated side was moved down to 60~100cm soil depth for FI coupled with FN when nitrogen and water were applied within the same furrow, and that of nonwater supply side was gathered in 0~40cm soil depth for FI coupled with FN when nitrogen and water were applied to different furrows. Compared with CI, AI reduced soil nitrate nitrogen under the plant in 40~80cm soil depth by 9.9%~14.4% for different nitrogen supply methods. Compared with the other treatments, AI coupled with CN or AN maintained soil nitrate nitrogen in 0~40cm soil depth for a longer time during maize growth. Soil residual nitrate nitrogen in 0~100cm soil depth at harvest was comparable between AI coupled with CN and AI coupled with AN, and the residual of them was reduced by 11.7%~27.3% compared with those of the other treatments. Therefore, alternate furrow irrigation coupled with conventional or alternate nitrogen supply brought a relatively reasonable spatial-temporal distribution of soil nitrate nitrogen during maize growth, and lowered soil residual nitrate nitrogen at harvest.