In recent years, sustainable development has become a critical area of concern in the aviation industry. The number of airlines that incorporate sustainability into their business is increasing to enhance their market positions and profitability. Sustainability reporting is an efficient and straightforward way to understand how airlines do in related fields. In this paper, we develop a scoring system for the environmental components in airlines’ sustainability reports. Then we build a statistical model to test the relationships between airlines’ sustainability reporting performance and multiple factors. The thesis finds that the size of an airline (RPK) and the environmental performance index (EPI) of its home country are both positively correlated with the airline’s sustainability reporting performance. Besides, if an airline is listed in any market, it has better reporting performance. Furthermore, Star Alliance members have a better chance to perform better than other airlines in their sustainability reporting. Contradictory to intuition, full-service carriers and low-cost carriers are not significantly different in terms of their reporting performances.