Based on practical experience in the manufacture of civil aircraft and research on FAA and CAAC regulations, this paper analyzes the authorization functions of designees of FAA and CAAC in the field of conformity inspection, which explained from regulatory requirements, the classification of designees in the field of conformity inspection, the specific authorization functions and the reasons for these differences. Although there are differences between the two CAAs of the authorization functions in the field of conformity inspection, only the airworthiness management has the suitable level for the aviation industry, that is better for the development of aviation.