Abstract: During the process of natural gas treatment in Keshen Treatment Plant, the wax precipitation from J-T valve and low-temperature separator caused the blockage of system, which limited the capacity of natural gas unit and caused unqualified hydrocarbon dew point of exported gas. The wax prevention process was studied to solve the problem. Through experiments and HYSYS software simulation, the specific causes of wax blockage were analyzed. It was concluded that the natural gas components in Keshen block were discontinuous. Due to the lack of C₅ to C₈ components, polycyclic aromatic hydrocarbons existed in the gas phase and could not be dissolved and separated, so it was easy to condense and precipitate after entering the low temperature environment, which eventually led to the internals blockage of the low temperature separator. Through the experiment, field operation experience and theoretical calculation, the technical solution route was formulated according to the principle of similar compatibility principle. Through HYSYS simulation analysis, light hydrocarbon was injected from the front of the feed gas air cooler to supplement the missing components, so as to solve the problem of wax plugging, and the design capacity of a single treatment unit was restored. The accuracy of component analysis of wellhead natural gas was very important for the design of processing device. The requirement for component analysis of newly developed gas field was increased from C₇ to C₃₀, and corresponding component analysis method was formed. The research results were successfully applied to Keshen Treatment Plant with wax plugging, and good results were obtained, which has a reference for the construction of similar waxy gas field.