Abstract: The electricity spot market with the unilateral bidding by power generators is a market model commonly used in my country's electricity spot market pilot provinces. The participation of the Incentive-based Demand Response (IDR) in the market as a load-side resource may improve the system flexibility and needs to be incorporated into the current market with one-sided bidding. In view of the problem that different IDR incentive strategies will lead to different efficiency losses, this paper constructs an IDR implementation market structure that incorporates load-side resource participation in the unilateral bidding spot market, and constructs the market efficiency loss ratio to quantitatively analyze the impact of different incentive strategies on the market. Considering the different game modes of the Independent System Operators (ISO), the generators and the IDR users, a minimum efficiency loss incentive demand response model based on the Stackelberg equilibrium analysis is established. Finally, through the 3-node and the 118-node network the effectiveness and rationality of the method are verified. The mechanism proposed in this paper will gradually introduce user-side participation elements in a planned and step-by-step way in the electricity spot market with unilateral bidding, and realize the demand response incentive intensity design with the lowest overall efficiency loss in the market.