Through the literature research as well as field survey and interview, the engineering requirement, resource integration, organizational synergy and institutional guarantee are chosen to be the key synergetic elements. The synergetic mechanism model consisting of cooperation mechanism, benefit mechanism, motivation mechanism and institution mechanism is also constructed. Besides, the effective operation of synergetic mechanism is proved to be functional to improve the ability and efficiency of technology innovation for major construction projects. This paper which is part of the theoretical research on the technology innovation network for major construction projects will provide some valuable theoretical guidance for the technology innovation practice and the technology innovation policy make of the industry.