The impact of waste landfill on climate change was analyzed by comparing the amount of CH4 emission from landfill with the potential energy conversion. For this analysis, compulsive collection and surface emission amount of CH4 were used against Sudokwon Landfill Site 2nd Landfill, which is currently under operation in the Republic of Korea. As a result of the estimation, the total CH4 amount which can be collected from the Sudokwon Landfill Site 2nd Landfill during 2001-2035 is 3,068×106 N m3. During the same period, the total CH4 emission amount from the landfill slope, intermediate covering and final covering is 899×106 N m3. Especially, 95% (854×106 N m3) of the total surface emission is emitted during the landfill period 2001-2015. After final covering, in the period of 2016-2035, only 5.0% (45×106 N m3) is emitted. Additionally, as a result of analysis by comparing the surface emission amount from the route of the slope, intermediate covering and final covering, 92.8% (834×106 N m3) of CH4 is emitted from intermediate covering during landfill operation. The CH4 emission from the surface of Sudokwon Landfill Site 2nd Landfill during 2001-2035 can be converted to 32.9×106 Ton in CO2 bases. On the other hand, on CO2 bases, the reduction amount of global warming gas by converting compulsorily collected CH4 to energy source is about 19-33% of surface emitted CH4. It can be concluded that to improve the landfill method as a waste treatment methodology which can better adapt to the climate changes, various research and development on the intermediate covering system along with the fundamental enhancement on present landfill facility establishment standards and operating guidelines are required.