Abstract: This paper introduced the operation problems of Guang'an LNG plant due to the components change of feed gas, which included heavy hydrocarbon blocking at low temperature and ethane adaptability. The phenomenon and reason of the problem were analyzed, and the solution and application effect were discussed. After adjusting the process parameters and adding activated carbon to remove heavy hydrocarbon, the plant ran steady. The components of the feed gas has great effect on the operation of LNG plant. Therefore, the analysis and forecast of feed gas components change are very important to new LNG plant.