The work aims to remove defects usually present on primer/finish coatings including peeling, blistering, cracking on the surface of aluminum alloy and composite material substrate. The designing defects of the closed thin-gauge skin structural components were figured out based upon structural design rationality analysis of defective coating components. By analyzing process technique for aluminum alloy and composite materials, effects of protective layer generated by aluminum alloy anodizing on coating properties were validated in contrast test method. By improving the surface pretreatment technology, release agent left over the composite materials was verified to be main factor affecting coating adhesion. The coating toughness formula was adjusted and coated on different substrates and relevant structural components to improve adaptability of coating to stress changes. Coating properties featuring in improved design and process were verified in combined loading test method “thermal shock+vibration+shock+dampness-heat”, which could be used to simulate testing state of the product. The coating was completely free from delamination and cracking after venthole was designed reasonably, gas expansion effect in the closed thin-gauge skin structural components was eliminated, and coating toughness and surface pretreatment of aluminum alloy and composite materials were improved. Closed thin-gauge skin structural components shall be equipped with venthole inside and outside. Complete removal of surface release agent pervious layer on composite materials and anodic oxide film on aluminum alloy, and selection of coating system exhibiting good toughness can improve environmental adaptability of surface coatings on aluminum alloy and composite material composite components.