Abstract: In order to identify the characteristics of machinery operation and pollutant emissions, a new emission estimation method for port machinery was developed by conducting field study of ports in the Pearl River Delta(PRD) region.The new method based on the fuel consumption rate of port operation modes and types of machines was validated by comparing the fuel consumption estimated with the statistical fuel consumption in ports and other methods.The results showed that the estimated fuel consumption agreed with the statistics well in the PRD region, with slight relative error of -5.9%-6.8%.For those in other areas, the relative errors of fuel consumption were also in a reasonable range, being -35.8%-53.8% and -17.5%-2.6%.A cargo handling equipment emission inventory in the PRD region for the year 2014 was developed using the new method.The results showed that the total emissions of SO₂, NO_x, CO, PM₁₀, PM_2.5 and HC were 633.6, 4610.6, 3391.2, 226.9, 216.0 and 728.8 t, respectively.Compared with bulk terminals, container terminals had a higher contribution.In the container terminals, container cranes and yard tractors were the main contributors.Through comparison and uncertainty analysis, the emission inventory in the PRD region developed in this study was proved to be reasonable.The method established in this study effectively makes up the deficiency of machinery holdings and fuel consumption rates obtained from incomplete statistical data.It provides a reliable alternative for emission inventory development, pollutant reduction assessment and air quality management.