The invention provides a large-area society-wide power consumption prediction method based on a grid method. According to the method, by taking electric quantity density as a representation amount, the disadvantages of load-based result prediction in conventional electric quantity prediction, small information amount and inaccurate result are overcome. The method has a guidance effect of improving planning, enables prediction work of society-wide power consumption to be closely combined with the reality, and prevents large-scale resource-consuming and labor-consuming data statistics. The method is simple, the flexibility is high, through grid division, local society-wide power consumption can be more effectively known, and the method has certain social benefits. At the same time, the method also provides a certain powerful basis for prediction of a power load and planning work of a whole power grid. The steps are simple, the operation is convenient, and the practicality is high.