Abstract: Flight delay is delay of performance, whose definition should adopt reasonable expectation doctrine. Chinese law on the classification of delay isn't suitable. The international doctrine of liability fixation about flight delay insists on the doctrine of presumptive. The EU has experienced initial, mature and perfect periods in the improvement of flight delay responsibility. And now it is improving the protection for passengers by revising regulations and judiciary cases, and in the future it will further strengthen passengers' rights. The complaints caused by flight delay have been more and more serious in China due to the low level of legislation and lots of legal blankness,so the airlines usually make use of the legal blankness and avoid undertaking liability. Recently, CAAC released the new legislation draft, the first special legislation about flight delay, which reflects the legislative trend of strengthening the protection of passenger rights but it is still on the lower stage of EU's legislative development. By comparing China with EU on related legislation and practice, the paper makes pertinent suggestions on the liability system and specific practice about Chinese flight delays.