Under the increasing demands as well as resource shortages in today’s society,energy-saving technologies in building water supply and drainage construction plays a vital role.Through the rational application of energy-saving technologies,energy consumption in water supply and drainage projects can be significantly minimized and wastage of water resources can be reduced.This will play a very promising role in promoting sustainable development of resources and environmental conservation in the modern era.This paper analyzes the application of energy-saving technology in building water supply and drainage construction,with an aspiration to make energy-saving technology more reasonable in today’s building water supply and drainage projects and to improve the quality of water supply and drainage construction projects,while achieving effective environmental protection.