Abstract: As China’s electric power spot market is at an initial stage,there exist contradictions between the bidding mode of singleunit quotation and the physical operating characteristics of cascaded generating units. When all generators in the market make price declarations and settlements independently,the dispatching and clearing results may be inconsistent with the operation performance of the actual unit group,which may bring difficulties to the unit group quotation,and lead to serious dispatching deviations and waste of actual resources. Therefore,for the power generation resources coupled with resources such as cascade hydropower units,this paper proposes a bidding mechanism based on aggregation nodes. First,the quotation mechanism and quotation strategy of the aggregation node are introduced in detail,and then the spot market clearing model of the aggregation node quotation is established.Finally,through the IEEE5 simulation,it is proved that the bidding mechanism based on the aggregation node can make the market clearing result reflect the generating units’ intention to trade,effectively allocate cascade hydropower generation resources,and improve the transaction efficiency of power spot market.