Abstract: With the continuous development and improvement of the national carbon emission trading market, the impact of carbon cost on the production and operation of LNG terminal enterprises becomes unignorable. Herein, study was performed based on an LNG terminal phase-Ⅱ project in Yangtze River Delta with the proposed processing capacity of 600×104 t/a. Specifically, the chronological development level of carbon emissions in each year during its operation cycle was measured with the emission factor method based on the historical annual carbon emissions of the phase-Ⅰ project that has been put into operation. Meanwhile, consideration was given to the impact of price level in future carbon trading market on the investment return of LNG terminal. The research results show that the proportion of carbon cost with consideration to the carbon emissions of LNG terminal in the operating cost of the LNG terminal increases year by year with the influence of the carbon market price, with the maximum of 4.11%, which has a significant impact on the operating cost of LNG terminal. If the internal rate of return on total investment(after tax) remains at 8.00%, the LNG processing cost will increase by 0.51%. On this basis, sensitivity analysis was conducted for the future carbon emission price, which shows that the impact of carbon emission price fluctuation on LNG processing cost is within±0.1%. Generally, the carbon cost has a certain impact on the operating and processing costs of the LNG terminal, which could provide a reference for the economic evaluation of an LNG terminal project with carbon emission cost considered.