This project is located in severe sea conditions area，with deep water，large waves，frequent strong typhoons and few days of offshore construction，making the construction extremely difficult. Aiming at the breakwater structure under severe sea conditions，based on the analysis of the actual sea conditions and construction requirements，super large double-layer accropode armour structure is innovatively proposed. The form and specification of the cushion and its influence on the armour stability，the safety of the double-layer accropode armour structure and the installation density of the armour block are discussed. The results show that the double-layer accropode structure is safe and reliable，and can better meet the needs of typhoon prevention during construction. The weight difference between the upper and lower layers should be increased as much as possible，and the weight of the upper layer accropode block should be about 3 times or more than that of the lower layer. For the super large double-layer accropode armour，the installation density of upper blocks can be appropriately reduced. The research results can be used as a reference for similar projects.