In terms of the intuitionistic fuzzy multi-criteria group decision making problem where the weight information of criteria is completely unknown, considering the shortcomings of the classical intuitionistic fuzzy entropy formula and the MULTIMOORA model, a new intuitionistic fuzzy entropy formula is proposed to fully describe the intuitionistic and fuzzy information of intuitionistic fuzzy numbers. A dominance convex combination operation is defined, and the MULTIMOORA model is extended to solve the multi-criteria group decision problems. In a framework of complex system under intuitionistic fuzzy environment, the evaluation index system of airport fire station site selection is constructed, and then the evaluation model of airport fire station site selection based on the entropy weight intuitionistic fuzzy extened MULTIMOORA is proposed. The case analysis shows that the proposed method is reasonable and effective, which provides a new idea for the site selection evaluation of airport fire station.