Choosing material is important during the development of an aircraft and the materials which are appropriate or not influence the performance of the aircraft. So many factors should be considered. The amphibious aircraft structure design is in accordance with fatigue and damage tolerance design. This paper analyses the load condition and service circumstance of the amphibious aircraft and the requirement of static strength properties, fatigue and damage tolerance properties and corrosion resistance properties, considers about factors such as aluminum characters, airworthiness, cost and material supply, then the scheme of choosing aluminum on structure of amphibious aircraft is presented.