The invention discloses a power market clearing method and system, and relates to the field of power market technical support systems. The power market clearing method comprises the following steps: analyzing a market clearing rule, decomposing the market clearing rule into a plurality of related factor components, and defining a base class and a base class interface of an algorithm component; andestablishing an algorithm component object library, selecting different component object classes to form corresponding market clearing rules, and forming a market clearing rule library; and extracting data of each component object required by market clearing calculation from the market clearing rule base by the market clearing engine, analyzing the market clearing rule through the algorithm engine, calling the component objects in the market clearing calculation data pool, calculating a market clearing result and outputting the market clearing result. According to the power market clearing method, market clearing results of different regions and different market development stages can be rapidly calculated, and higher flexibility and expandability are achieved.