Abstract: In recent years, the economy and science and technology have developed rapidly. The construction industry, as the pillar industry of my country's economy, is also making continuous progress. The application of green energy-saving and environmental protection technologies has been increased in the construction industry. HVAC is an important component of green buildings. Part of it plays a key role in engineering. Combining the application value of green buildings, it is necessary to maintain resource conservation in the construction of engineering projects, increase the utilization rate of renewable resources, and promote energy conservation and environmental protection in the construction industry. At present, more and more people have begun to pay more attention to the energy-saving control of HVAC in green buildings, using effective measures to achieve comfort in living, while enhancing the value of energy saving and environmental protection in the construction industry, and reducing resources due to HVAC projects. Consumption provides a basis for the sustainable development of green buildings. Based on this, this article analyzes the energy saving of air conditioning systems in green buildings for reference only.