Predication of water consumption used in agriculture is significant to set the planning of configuration optimization of water resources. In order to forecast water consumption used in agriculture exactly, support vector machine and genetic algorithm is proposed to forecast water consumption used in agriculture, where genetic algorithm (GA) is used to select the parameters of support vector machine. The experimental results demonstrate that the proposed GA-SVM model provides better prediction capability and is therefore considered as a promising alternative method for forecasting water consumption used in agriculture.