According to the requirements of “Airworthiness Standards: Transport Category Airplanes” by CAAC, the assessment on ditching floatation characteristics have to be provided to ensure the occupants can leave the airplane and enter the life-rafts. The regulation requirements, the method and procedure of model test for ditching floatation characteristics is introduced in this paper. The application result analysis is also presented .This is of important influence on the airworthiness certification of ditching floatation characteristics for transport category airplanes.