Carbon dioxide is a variable gas, and has increased by about 12% every year since 1958. As the atmospheric concentration of carbon dioxide has steadily increased, it is regarded as the major cause of global warming. To reduce the emission of carbon dioxide that is the major cause of global warming, the emission characteristics of carbon dioxide need to be investigated. Especially, the carbon dioxide emission of the equipment used in the execution stage of a construction project is in some degree proportional to fuel consumption, but there exist certain factors that are not proportional to fuel consumption. The methods for calculating carbon dioxide emission include a method using chemical formulas, a method using the Intergovernmental Panel on Climate Change (IPCC) emission factors, and a direct measurement method. Among these three CO2 calculation methods, the indirect methods have the advantage of easy calculation, but the disadvantage of low reliability, while the direct method has the advantage of accurate information, but the disadvantages of requiring a lot of time and cost and the limitations of measurement. In this study, to overcome the disadvantage of the indirect measurement methods, CO2 emission was measured using the direct measurement method, and the CO2 emission characteristics of equipment were analyzed. Also, by comparing them with the values calculated using the indirect methods, the differences between the direct method and the indirect methods were analyzed.