Building energy efficiency is an important part in Chinese strategy of sustainable development, and because of their high energy consumption.A lot of new building energy saving technologies will be fully used in Tianjin Eco-city, the buildings will be constructed in accordance with green building standards to realize the comprehensive utilization of renewable energy.In the paper, residential buildings are calculated of the annual heating and cooling loads, and for CO2 emission reductions and co-benefit calculation by using the simulation software.Then, according to the LEED standard of America, the constructions of Eco-city in Tianjin were scoring.Through the comparison and grading, it can be analyzed and evaluated of green architecture.It has some reference value for developing low carbon buildings, realizing of energy-saving construction, full utilization of renewable energy and low-carbon construction in China.