Nowadays, with all the climate change problems that we face worldwide, engineers from different specialists work together towards Sustainability and finding solutions, and investigating its environmental impact thoroughly. Architectural, Chemical, environmental, civil engineers have always been closely linked in designing and constructing buildings. Geothermal energy is a local, resilient, reliable, ecologically benign, and sustainable form of the renewable energy system. This type of natural energy could be generated from the earth's heat and takes a variety of purposes, including building heating and cooling, electricity generation, supplying warm/cold water for agricultural products in greenhouses, as well as balneological usage. Furthermore, geothermal energy isn't affected by weather and could provide electricity and heat nearly constantly through the year. This study intends to investigate the opportunity of using geothermal energy in Iraq under the ground represents one of the sustainable energy resources we can use it will be a significant environmental benefit in our housing in air conditioning applications. This review gives a summary of geothermal energy systems in general. Topics addressed include: an introduction to the environments and the energy, also their relationship, a geothermal energy history brief, an overview of geothermal energy systems throughout the world and also through Iraq, and an overview of geothermal systems environmental impacts as well as the environmental impact of Sustainable buildings architecture design, are just a few of the topics covered. Hence, the achieved conclusions of this review can make changes towards sustainable environmental design.