Tom Green County is a county located on the Edwards Plateau in the U.S. state of Texas. As of the 2020 census, its population was 120,003. Its county seat is San Angelo. The county was created in 1874 and organized the following year. It is named for Thomas Green, who was a Confederate soldier and lawyer. Tom Green County is included in the San Angelo metropolitan statistical area; the county is home to Goodfellow Air Force Base, as well as Angelo State University, part of the Texas Tech University System.

The Edwards Plateau is a geographic region forming the crossroads of Central, South and West Texas, United States. It is named in honor of Haden Edwards. It is bounded by the Balcones Fault to the south and east; the Llano Uplift and the Llano Estacado to the north; and the Pecos River and Chihuahuan Desert to the west. San Angelo, Austin, San Antonio and Del Rio roughly outline the area. The plateau, especially its southeast portion, is also known as the Texas Hill Country.