Recently, site selection studies for the purpose of industrial development have become very prevalent. Specifically, thermal power plant site selection studies have attracted a lot of attention. In these studies, several different parameters are included. In the first phase of the current study, different types of thermal power plants and their configuration functions are explicated. In the second phase, the current status of Iran’s thermal power plants and their environmental impacts are explored. In the next phase, important site selection parameters influencing thermal power plant operation and the environment are categorized as: a) Environmental Parameters (Slope, Water, Fault, Meteorology, Soil, Geology and Land use), b) Socioeconomic Parameters (Fuel, Access Road, and Population Centers), c) Technical Parameters (Power Transmition Lines, Power Consumption Load and Elevation).Finally, a thermal power plant environmental model is developed. Based on this model, potential sites for the construction of a thermal power plant are categorized as suitable, Quantitative suitable and unsuitable area.