Arming at the problem of not considering meteorological factors when the trend change method is used to forecast power load, a weighted method of load forecasting based on change trend and meteorological factors is proposed, which is modified the power load forecasting method based on the change trend by considering the three meteorological factors of temperature, humidity and weather type. Two problems of the power load forecasting method based on the change trend including failure to consider the influence of external factors and cumulative error by trend forecasting method are analyzed. The detailed calculation steps are given based on fully studying the daily average load change rate and the average load change rate between points, which is applied to an ex-ample of power load forecasting in a certain area of northern Jiangsu. Finally, the results show that the average relative error of the method is 3.42% with high forecasting accuracy and small data fluctuating, which verifies its validity and feasibility.