Abstract: With the integration of various energy such as heat and natural gas, the types of decision-making entities participating in the integrated energy market transactions are becoming more and more complex and diverse. However, the traditional optimization theory and most classical game theories can no longer solve the above increasingly complex behavioral decision-making problems of multiple entities. Aiming at how integrated energy retailers select strategies to compete in retailing energy sales, using the emerging evolutionary game theory, an evolutionary game model of retail-side market is established under the integrated energy competitive agency model, which takes the integrated energy retailers with limited rationality and information access as the research objects. Through theoretical derivation, the ranges of optimal competition strategies are obtained. Solved by the iterative algorithm based on the forward Euler formula, the case analyzes the evolutionary results, evolutionary time of integrated energy retailers and their influencing factors. It verifies the effectiveness of the evolutionary game theory in the behavioral analysis of market entities, and provides suggestions for the policy formulation of government and the behavioral decision-making of entities in the integrated energy market.