To avoid boundedness and one-sidedness in the research on the development of USA's sixth-generation fighters，it is proposed based on methodology that we should do the research by integrating the three aspects together，i.e.，tracking and analyzing the development trend of USA's sixth-generation fighters and relative technologies，summarizing the US army's requirements on the sixth-generation fighters (Request for Information) and the corresponding response of the industrial communities，and concluding the development histories of each generation of fighters in the USA and focusing on current development of the sixth-generation fighters.Our viewpoint is demonstrated in the end.