Abstract: The paper described the risk assessment, design, and consruction on Kelamayi-Wulumuqi pipelines for oil pipeline to gas pipeline technological reform project. The work deals with the route and stations reform and corrosion control based on inspection and assessment for Kelamay-i-Wulumuqi pipelines. The article systematically introduces the engineering's investigation, design, construction and operation. As compared with the construction of a new gas pipeline, the engineering has saved more two hundred million RMB yuan with effectively economic benefit. As the first oil pipeline to gas pipeline technological reform engineering in home, the engineering practice can provide a important reference basis for other oil pipeline to gas pipeline technological project.