Relying on major projects, industrial technology catch-up in some fields has been achieved in China. State-owned enterprises are special market entities undertaking political functions in major projects. Different from previous research focusing on the role of the government or the market, the role mechanism of state-owned enterprises in leading industrial chain integration to realize industrial technology catch-up is investigated. The analysis is performed based on a longitudinal single case study of CGN from the perspective of integration. The conclusions are as follows: ① Driven by the government’s intention and market demand, the dominant role the integration of industrial chain is played by state-owned enterprises by relying on major projects; ② the basis of state-owned enterprises’ leading industry integration is constituted by the interactive development of resources, network location and engineering technology capability; ③The mode of state-owned enterprises leading integration has undergone a phase evolution from contract regulation to platform governance; Meanwhile, the dual goals of enterprise''s own ability development and industry technology catch-up are realized during the evolution. Valuable insights for better playing the leading role of state-owned enterprises are provided by the case study analysis.