Abstract: In order to solve the problem of group decision making in which the criteria weight and the weight of decision makers are completely unknown in the intuitive fuzzy environment, we propose a multi-criteria group decision method based on improved intuitionistic fuzzy entropy and information integration operator. Firstly, using the intuitive fuzzy numbers, language variable method and quantitative index value conversion formula, we normalize the initial evaluation criteria for decision makers. Secondly, we introduce improved intuitive fuzzy entropy to determine the criteria weight and the weight of decision makers. Thirdly, we use the intuitionistic fuzzy weighted average operator and the intuitionistic fuzzy ordered weighted average operator to integrate the intuitive fuzzy decision matrix, and use the improved score function to optimize the ranking of options. We prove the feasibility of this method theoretically, and verify the effectiveness of the method by an example.