Due to the variety and the randomicity of its influencing factors, the electricity demand forecasting is a difficult problem for a long time. In order to improve the forecast accuracy, the paper proposes a new load forecast model based on GM(1,1) and support vector machine. First, the GM(1,1) is used to forecast the load data in the model. And then according to factors and historical load vector, support vector machine load forecast model is established to forecast the residuals of GM(1,1) and modified the forecast results of GM(1,1). Case analysis shows that the forecast method is suitable and effective, improving prediction precision compared with GM(1,1) and support vector machine, and has better utility value in mid-log term load forecast.