Abstract: The European Court of Justice(ECJ) released a preliminary ruling made in the proceedings brought by the Air Transport Association v. SS for Energy and Climate Change on 21 December 2011. Broadly speaking, ECJ’s preliminary ruling addressed two questions:first, only certain provisions of the Open Skies Agreement (article 7, article 11(1) and article 11(2)(c), article 15(3))and three principles of customary international law(namely the sovereignty of States over their airspace, the illegitimacy of claims to sovereignty over the high seas and freedom to fly over the high seas)may be relied upon for the purposes of examination of the directive’s validity; second, the European Union Aviation Emissions Trading System Directive is consistent with these international laws. Considering many obstacles and uncertainties inferred by this preliminary ruling for Chinese civil aircraft industry to initiate the similar litigation, Chinese civil aircraft industry should push its government to seek international cooperation and actionable aviation emission reduction schedules to cope with the EU aviation emission trading system.