As the application of more and more advanced composite materials in civil aircraft and the increasing importance and integration of electronic and electrical equipment used in civil airplane, the lightning protection design of airplanes becomes more and more important. The 23.867 of CCAR 23 gives the airworthiness requirements of the lightning protection for civil airplane’s airframe structure. This paper studies the background and process of the formulation and revision of the clause, and clarifies the substantial airworthiness requirements of the clause. Due to the differences in use and design characteristics between the part 23 airplane and the other airplanes, there are still differences in lightning protection design and compliance verification between them, so the basic process of airworthiness certification of lightning protection against direct effects, and the acceptable means of compliance were given for the part 23 airplane, The principal activities, reference documents, key concerns and technical points of lightning protection design and certification process were put forward,which provides a reference for the design and airworthiness certification of lightning direct effect protection for civil aircraft.