The invention relates to an electric power system energy management system historical data storage method adopting a two-dimension table, and belongs to the technical field of electric power system energy management system databases. According to the method, firstly, energy management system historical data information is extracted from a real-time database of an electric power system, the number of data tables in the database required by the large-category data is determined according to the maximum allowed storage line number of the database storage capacity and the number of historical points in the large-category data, and a historical value table is built, wherein the fields are sequentially the historical point names and the table names, i.e. the historical tables corresponding to the historical points, and the line numbers of the historical points in the historical value tables. The data storage method has the advantage that the pressure of the database is obviously reduced on the basis of not increasing the hardware cost. Through building the mapping relationship between the data value and a data dictionary of the historical points, the database can be fast accessed, and in addition, the response speed of the system is accelerated.