The invention discloses a load combination forecasting method and device. In the method, a first weight value and a first threshold value of a first calculation formula and a second weight value and a second threshold value of a second calculation formula are initialized by obtaining initial predicted values of different single forecasting models, the initial predicted values are taken as input, practical predicted values are calculated through the first calculation formula and the second calculation formula, load predicting is conducted by comprehensively utilizing the different single forecasting models, and therefore the defects generated when only a single forecasting model is used for conducting load predicting are overcome, and the accuracy of predicted load data is improved.