With the introduction of the “carbon peak and neutrality” in the 14th Five-Year Plan，China's infrastructure construction is driven towards a green and low-carbon direction，and the life cycle assessment(LCA)method is gradually being applied to China's construction industry as a comprehensive environmental impact assessment tool.Based on the life cycle assessment theory，we select an inland river port project in the upper reaches of the Yangtze River as the research object，and divide the whole life cycle of the port project into the construction phase，operation and maintenance phase and decommissioning phase to analyze the carbon emission sources and estimate the carbon emission.The results show that the life-cycle carbon emissions of the port project are 86,700 t CO2-eq，with 39.4%，56.7% and 3.9% for the construction，operation and maintenance and decommissioning phases respectively.The 95% confidence interval for unit carbon emissions is 651.92 to 745.21 kg CO2-eq/m2，with a median value of 698.14 kg CO2-eq/m2.The uncertainty in the inventory data is little，and the sensitive factors for port carbon emissions are concrete and electricity.The carbon emission evaluation results are generally good，and can be used as a relevant basis for the subsequent formulation of carbon emission reduction policies.