Taking Mizhi County as an example and the year of 2005 as base period of planning, this paper made a prediction of farmland demand in 2010 and 2020 using grain security method, supply-demand balance method, and trend extrapolation method. In addition, it built a fixed weight combination model to make scientific summary of three prediction results. Finally, it predicted the farmland demand of Mizhi County in 2010 and 2020 will be 40 967 hm2 and 36 556 hm2, which can provide basis and reference for determination of farmland protection area in the land use planning.