The airlines constitute the central element of the air transport production chain. Brazil has been consolidating as one of the main markets of the sector in the world, with rising annual growth rates of passengers since the beginning of the 21st century. Despite this positive scenario of market growth and the countryâs great experience in the commercial airline sector, there is a turbulent environment in this industry, with bankruptcies, consolidations and acquisitions of companies. The goal of this article is to analyze the efficiency of this industry, through the data envelope analysis (DEA), in view of the market share currently possessed by airline companies. As a result, we observed that the largest companies in the sector are not operating on the efficiency edge, and so we suggest an increase in this aspect to make them more attractive and competitive in their market area.