Abstract: In this study, emission tests were performed on 45 typical construction equipment by using portable emission measurement system (PEMS) to obtain their emission factors. Test cycles include idling, moving and working. Result showed that variations occurred on moving and working cycles, while most of peaks happen on working cycle. Emission characteristics based on fuel consumption were analyzed and emission inventory were calculated according to the measurement data and fuel consumption survey data. The results show that fuel-based emission factors of CO and HC are higher on idling operating mode, while NO<sub<<em<x</em<</sub< and PM are higher on working mode. Fuel-based emission factors of CO, HC, and PM are higher from bulldozer than those from other equipment. Compared with stage Ⅰ equipment, the fuel-based emission factors of stage Ⅱ equipment lower to a certain extent.