Abstract: The flexibility of demand-side resources needs to be aggregated through a feasible region aggregation technique to participate in the spot market. This paper presents a feasible region aggregation method of demand-side resources considering flexibility revenue. Firstly, a feasible region approximation method based on Zonotope is presented, which could approximate the feasible region of power, state, and climbing constraints effectively. Secondly, the revenue of flexibility in different periods is considered, and the feasible domain with variable weight is designed to approximate the optimization objective. Finally, the efficient aggregation of the feasible domain of demand-side resources is realized, which provides the system with high-value flexible resources. The validity of the proposed method is verified based on real electricity price data and the energy storage model.