Heating Ventilation Air Conditioning (HVAC) is an important part of modern architecture, and it is also the most important energy consumption system in the use of modern buildings. With the continuous development and progress of the society, energy saving and emission reduction has become a hot topic in today's society, and people pay enough attention to the application of building HVAC energy-saving technology. Through the application of this technology, the effect of reducing building energy consumption is achieved. The author explores and analyzes the necessity and main advantages of building HVAC energy-saving technology, and puts forward an effective way to apply HVAC energy-saving technology, which is hoped to help reduce building energy consumption.