The invention discloses a weather prediction method used for a micro power grid system. The method includes a step 1 of collecting and storing local weather information Rt at a t moment regularly. Themethod also includes a step 2 of acquiring data whose address is identical to that in the step 1 and whose time point is identical to that in the step 1 from State Meteorological Administration, namely, acquiring and storing history true weather information from the State Meteorological Administration; acquiring State Meteorological Administration history predication weather information corresponding to the history true weather information from the State Meteorological Administration, wherein the history true weather information from the State Meteorological Administration is indicated by F1t; acquiring further weather forecasting information of the State Meteorological Administration which is indicated by F1't. The method further includes a step 3 of predicating the weather information of the next moment by adopting a smooth index method; a step 4 of fitting an optimization weather information regression model by taking F1t, F2t as the input while taking Rt as a target line by utilizing a linear regression method, and predicating weather information of a future period of time according to the model. The method can obtain more accurate weather predication data.