The invention relates to a system and a method of fused magnesium production energy management based on BOM (Bill of Materials) and MRP (Material Requirement Planning) algorithms. The system comprises a sales management module, an inventory management module, a procurement management module, a product BOM module, an MRP computing module, a production planning module, an electric energy planning module, a production dispatching module, an electric energy counting module and an electric energy monitoring module; the fused magnesium production energy management method comprises the steps: performing MRP computation according to fused magnesium BOM, sales order quantity demand of the fused magnesium, delivery date of the fused magnesium, available inventory quantity information of the fused magnesium, available inventory quantity information of magnesite ores and available inventory quantity information of graphite electrodes; and generating electrical energy requirement planning, procurement planning of raw materials and production planning. According to the system and the method of fused magnesium production energy management based on BOM and MRP algorithms, the formulating efficiency and accuracy and the operability of the production planning, the procurement planning and the electric energy requirement planning of fused magnesium enterprises can be improved greatly; the plans match with the sales order requirement, so that the production can be organized as planned and the just-in-time delivery of the order is guaranteed.