System Integration is one of the most important parts of System Engineering, and it determines the success or failure of a large-scale engineering project. System integration of largescale engineering project concerns time, cast, risk, and so on. Time integration is more important and difficult among them. Aerospace Engineering is a typical kind of large-scale engineering and is in general divided into many subsystems. System integration process of aerospace engineering has many steps and impossible paths, and complicated relations exist among these steps and paths. Schedule delay and performance dissatisfaction resulting from system integration occur frequently in the system integration process of aerospace engineering. In this paper, firstly, two models (GAN model and InfoGap model) and strategies (Single Stage Integration strategy and Incremental Integration strategy) of system integration are introduced briefly; then, the models establishment and strategies design of system integration of aerospace engineering are discussed; finally, the correlative problems are analyzed.