The main manufacturer for the civil aircraft gives full play to self-airworthiness by establishing design assurance system, which ensures the safety of aviation product development to improve the quality of the products and keep it running with high quality from the whole life cycle. Based on the airworthiness requirements of both European Aviation Safety Administration and Civil Aviation Administration of China, this paper establishes the scheme of Design Assurance System combined the system of the main manufacturer for the civil aircraft. With common management system, Design Assurance System was established from aspects of Responsibilities, Activities, Organization, Resources, and Documentation System around three main functions as design, airworthiness, and independent supervision.