Before natural gas liquefaction,the raw natural gas needs to be purified to remove CO,2,H,2,O,H,2,S and heavy hydrocarbon(C,5, and above hydrocarbons,abbreviated as“C,5+,”) components in it,so as to prevent the above components from freezing and forming solid in the liquefaction section and blocking the pipeline and equipment.Taking a western liquefied natural gas（LNG） plant as an example,in view of the large variation and high content（mole fraction,the same as below） of C,5+,components of raw natural gas in the pipeline of the plant,the original C,5+,component removal process was reconstructed and designed based on the analysis and detection of raw natural gas components,and the designed C,5+, component removal process was simulated and calculated with Aspen Hysys software and applied to production.Finally,the components of purified natural gas in production were detected and analyzed.The research shows that the C,5+, component removal process combined with low temperature condensation pre-separation and high performance activated carbon adsorption is theoretically feasible.Under the condition that the C,5+, components of natural gas meet the requirements of liquefaction process,the C,2,～C,4, components are retained to the maximum extent,and the heating value of LNG is improved.In the simulation results,the C,5+, component content in the natural gas after C,5+, component removal is 0.007265%,which is similar to 0.0076%of C,5+, component content in the natural gas after purification in the actual production.