The invention discloses a method and a device for predicting regional electricity sales. The method comprises steps of performing determination of time domain and frequency domain characteristics on history electricity sale curves of regions to be predicted, performing clustering on each region to be predicted, wherein, in one cluster group, the characteristics of the history electricity sales curves of all region to be predicted are identical under the time domain and the frequency domain, and the characteristic is used as the characteristic label of the cluster group, and, for every cluster group, choosing a preset prediction algorithm corresponding to the characteristic label of the cluster group to perform electricity sales prediction on all regions to be predicted in the cluster group. The invention performs cluster partitioning on various regions to be predicted, adopts matched identical prediction algorithm to perform uniform prediction on the regions having same history sales curve characteristics, and improves the accuracy of the regional electricity sales.