As the importance of efforts to reduce carbon emission from buildings is increasing throughout the world, the plans for carbon reduction during the life cycle of a building are being discussed from various angles. The energy consumption of buildings accounts for 22% of total energy consumption and is showing a trend of continuous increase. Carbon emission, accordingly, is also on the rise. At this, an effort to minimize carbon emission through consideration to overall energy consumption of a building and reasonable environmental impact evaluation is required. This study, based on material saving models by stage of an apartment housing among structures that consist a green building, has analyzed carbon reduction amount according to energy saving plans by stage. The analysis was carried out on the reduced amount of carbon emission and the subsequent environmental impact according to energy saving through carbon evaluation in the stages of materials production, construction, operation, disposal and recycling for each energy saving model. This study aims at proposing the expected benefits of material and energy saving in buildings and the plans to reduce carbon emission from green buildings in Korea.