Severe load valley brings lots of difficulties to the system operation. The thermal generators undertake the deep peak regulation for valley filling traditionally when they are the main source of the generation. As the renewable energy develops quickly, the thermal generation keeps reducing in recent years. Most of the provinces in China chose to develop deep peak regulation market before a complete spot market. The current participants mainly include the thermal generators and the storages. In this paper, the load aggregator is proposed as the participants of the market to increase the load at the load valley. The operators clear the market with the co-optimization including both of the generators and the aggregators. The simulation has demonstrated the operation of the market model.