The Sichuan-to-East gas transmission project is the first systemic engineering project in China to explore and develop an ultra deep & high acid gas field on such a large scale, which contains natural gas exploration and development, centralized purification treatment, long distance pipeline transmission and comprehensive market development and utilization. It has the prominent characteristics of being oversize, extremely complex, highly risky and extraordinarily difficulty. Based on a brief introduction to the project's development background and construction scale, analyzing the main challenges of technology and management, this paper systematically accounts the construction ideas and the series of achievements of managerial and technical innovation. The construction and management experience of oversize comprehensive natural gas project about the ultra deep and high acid gas field exploration and development series techniques would surely be a useful reference for similar projects.