The assembly tools are the assembly process equipment for aircraft wings, fuselage, and other components. It has much higher assembly accuracy requirements than the aircraft components assembled on it. In this  paper, the assembly tools of an aircraft component are the research object. According to the technical concepts of digital twin, a digital twin-based assembly process model is constructed to install assembly equipment accurately. And considering related elements such as personnel, tools, standards, and inspection requirements associated with the tools assembly process, the assembly process of the tools is planned and simulated. The visual assembly process orders are used to guide the actual assembly process, and the information interaction and feedback are realized by establishing the association between digital space and physical space.