Abstract: The mechanism of energy conservation and emissions reduction of green transportation mode of the modern logistics as well as the research and application situations at home and abroad was introduced. With a case study of Beijing Sanjiadian Railway Freight Yard reconstruction, energy conservation and emissions reduction effects of green transportation mode of the modern logistics in Beijing were analyzed. The results showed that after this mode was put into use, Sanjiadian Railway Freight Yard could save 20 555 tons of coal equivalent and reduce 90.9 tons of PM_2.5 emission per year. Assuming an annual import of 15 million goods to Beijing, a saving of 883 864 tons of coal equivalent and a reduction of 3 908.7 tons of PM_2.5 emission per year could be obtained. On the basis of related statistics of the logistics industry in 2012, combined with the case study results and the effects of previous options in Beijing, the energy conservation and emission reduction potential of green transportation mode of modern logistics in China was projected. By revitalizing and reforming the fixed assets for existing idle 2 546 railway freight stations, this mode can save about 50 million tons of standard equivalent and reduce about 200 000 tons of PM_2.5 emission per year, while activating the economic development along the railways. In consequence, it can have great potential of energy conservation and emission reduction.