Abstract: In order to improve the commissioning efficiency of long-distance natural gas pipeline with ultra-large diameter, strengthen the risk control measures and optimize the configuration of commissioning resources, the commissioning process of China-Russia Eastern Gas Pipeline (Changling–Yongqing Section) (hereinafter referred to as "the middle section of China-Russia Eastern Gas Pipeline") was optimized based on the large pressure difference of commissioning, long commissioning time and frequent equipment operation, to enhance the commissioning operability of pipeline and the risk controllability of each node. During the commissioning of the middle section of China-Russia Eastern Gas Pipeline, a two-stage pressure regulation method was adopted in the station to solve the problem of excessive pressure difference of the pressure regulating valve. Meanwhile, the efficiency of steam heat exchange was improved by regulating the installation requirements for the insulation device of the pressure regulating valve, and thus the ice blocking risk of the pressure regulating valve was effectively mitigated. Besides, a natural gas replacement mode of "trunk line first and then station"was proposed for the long-distance natural gas pipeline, so as to reduce the risk of operation at night and facilitate the work of pressure stabilization and leak detection on site. In order to maintain the pressure of nitrogen seal, the adequacy of liquid nitrogen resource should be considered, if nitrogen is injected into the pipeline through a nitrogen injection vehicle. Generally, the research results could provide reference to the commissioning of long-distance gas pipeline with ultra-large diameter.