Abstract: The effective roughness for natural gas pipeline is an important parameter that technically calculates and assesses the economic benefit of pipeline with internal coating. At present, foreign and domestic design and/or determination methods on effective roughness for natural gas pipeline differ greatly. In this paper, the effective roughness scope to be determined for natural gas pipeline in developed countries and the latest research results of effective roughness are introduced. In the light of the effective roughness used in gas pipelines of China, taken Shaanxi-Beijin and Zhongyuan gas transmission pipelines as an example, an inverse calculation on effective roughness for the active pipelines has been carried out, and the constructive recommendation for the effective roughness of long-distance and large-diameter gas transmission pipeline has been presented.