This study analyzed the carbon emissions for two-star green residential buildings in Beijing. During operation period, the carbon emissions were calculated for air-conditioning, heating, lighting, elevator, and domestic hot water systems. Furthermore, the carbon emissions for full life cycle are also given in this paper based on the statistical method of big data. The results show that the carbon emissions during operation and full life cycle periods were 17∼21 and 21∼27 kgCO₂e/(m²·a), respectively. During operation period, the air-conditioning and heating systems accounted for 60%∼70% of the total carbon emissions, 26%∼30% and 4%∼9% for lighting and elevator systems, and the carbon emissions were lowest for domestic hot water systems.