The airport construction scale should be compatible with the level of social and economic development. If the scale of civil airport is too small, it will become a bottleneck of socioeconomic development. If the scale is too big, it will bring about waste of resources and hinder the sustainable development of society and economy. However, it is a complex and difficult task to evaluate the economic adaptability of airport construction scale. In view of the fact that there is no systematic research on the economic adaptability evaluation of airport construction scale, this paper sets up evaluation indices from the dimensions of demand satisfaction rate, supply efficiency and operation efficiency and gives the corresponding calculation formula by analyzing the intersection of relevant research fields and the suggestions of industry experts. In the meantime, this paper compares the economic adaptability of the construction scale of Chengdu Shuangliu International Airport and the three major airports in Beijing, Shanghai and Guangzhou by the fuzzy matter-element model and the multi-objective lattice-order decision-making. The comparison between the two evaluation methods reveals that all evaluation indices are reasonably constructed and can serve as technical basis for evaluating the construction scale of regional airports.