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A 0-1 programming model was proposed to optimize the deficit irrigation schedule. It is based on the concept of field water balance and the crop water production function, and introduces a 0-1 variable to describe the irrigation decision in possible irrigation periods. Microsoft Excel solver is applied for finding the solution. This model was applied in the irrigation schedule optimization of winter wheat in Xiaohe irrigation district in Shanxi Province. The result compares well with a previous developed simulation based optimization model, while the present model is much simpler in the solving procedure. Results demonstrate that the key period for winter wheat irrigation is the later jointing stage in early May. If the initial soil water content is low, the suitable irrigation time should be earlier in order to achieve higher crop yield. The evapotranspiration and relative crop yield increase with the irrigation volume, while the marginal yield decreases with the irrigation volume.