隨著國民所得提升，經濟蓬勃發展，台灣公路部門是運輸部門能源消費最多的部門，其中又以自用小客車及機車的使用量占最多，其次才是大客貨車，且其成長速度也相當快速，構成運輸部門能源需求的主要來源。交通運輸藉由能源的使用促進經濟活動及生活品質，卻使能源供給及環境惡化的壓力逐漸加重，而運輸活動對環境產生的負面影響，如NOX、HC、CO及CO2等廢氣的排放也與日俱增，溫室效應引起的全球氣候變遷。 本研究針對運輸部門中汽機車之CO2排放量為預估對象，主要是有鑑於CO2占汽機車溫室氣體排放量之首。首先本篇論文在CO2排放量的計算上，考慮以下幾個重要因素：汽機車年平均行駛里程數、耗能標準、排放係數、燃料使用量等影響因子。接著藉由所推估之汽機車數量，配合SigmaPlot軟體之迴歸分析及資料統計，最終預測未來2020年台灣公路運輸上汽機車CO2的排放量及每年度之燃油使用量。 未來政府在運輸部門中，可利用本論文CO2排放量之推估結果，作為制定減碳政策及環境管理上推行的依據，並提供各方學術領域人員做參考。 As the GNP rises the economy is growing rapidly. Taiwan’s highway department is consuming the energy highest in the transportation one. In which the using rate of the private automobile and motorcycle are in the most position and the secondary is truck which the growing rate is also quite rapidly. That consists of the energy requirement in transportation department as the main resource.Traffic transportation depends on the usage of energy to improve economy activities and the qualities of living but makes the energy supply and the environment deterioration worse off. However the transportation activities bring the negative effect, such as NOx, HC CO and CO2….etc. The emission situation of waste gas is getting worst. Greenhouse effect is caused to the global climate movement. This research is applied to the CO2 emission Volume of automobile in transportation department as the analysis factors. Due to CO2 is the top of the gas emission usage of automobiles. First all of, this thesis puts the point on the calculation of CO2 emission and considers several important factors as following: drive miles per averagely, standard of exhausted energy, emission coefficient, quantity of fuel usage…etc.And then we can refer to the estimation of automobiles quantities per the software “Sigma Plot”-regression analysis and statistics of data. Finally, let’s make a prediction for the CO2 emission usage of the automobiles and the quantity of fuel usage per yearly by Taiwan highway transportation in the future 2020 years. The government of transportation department in the future can use this thesis’s estimation result of CO2 emission Volume to be a record as a direction for reduced carbon policy and environment management and also offer information for academic fields study.