Abstract: In 1958, Federal Aviation Act of the U.S. stated that no air carrier shall violate the non-discrimination principle in air transport. The Supreme Court of the United States distinguished "overbooking oneself" and "performing the act of overbooking" to understand the non-discrimination principle. In terms of flight overbooking, internal and external consistency supervision standard is applied to all domestic and foreign air carriers in the field of international air transport. All passengers should be asked at the same time about their willingness to be denied boarding, and it is strictly forbidden to asking about only certain passenger' opinion or inquiring of passengers in turn. The precondition for boarding priority is that there are not enough volunteers. Boarding priority rules include "first book, first serve", "first come, first serve" and "comprehensive considering and balancing". The non-discrimination principle of overbooking could promote the development of the civil aviation industry and be an alternative for passengers to protect their own interests. China can learn from certain successful experience of USA.in overbooking when amending Civil Aviation Law.