Hudspeth County in the Trans-Pecos region of far-western Texas, is bordered by New Mexico to the north, the Mexican state of Chihuahua to the south, El Paso County to the west, and Culberson and Jeff Davis counties to the east. Sierra Blanca, the county seat, is seventy miles southeast of El Paso in south central Hudspeth County.

The county's center lies at approximately 31°32' north latitude and 105°28' west longitude, about twenty-four miles northwest of Sierra Blanca. Interstate Highway 10 and U.S. Highway 80 cross southern Hudspeth County from east to west, and U.S. highways 62 and 180 cross northern Hudspeth County from east to west. The Missouri Pacific and Southern Pacific railroads both enter southeastern Hudspeth County and meet at Sierra Blanca, from which point the latter line continues west to El Paso. The county covers 4,566 square miles of terrain in the Rio Grande basin that varies from mountainous to nearly level, with elevations ranging from 3,200 to 7,500 feet above sea level.

Soils in the lower elevations are alkaline and loamy with clayey subsoils that overlie limestone in some areas; thin and stony soils predominate in the mountains, and along the Rio Grande clay and sandy loams predominate. Vegetation includes short, sparse grasses, creosote bush, scrub brush, mesquite, and cacti, with juniper, live oak, and piñon at the higher elevations. Among the minerals found in Hudspeth County are barite, beryllium, coal, copper, fluorspar, gold, gypsum, lead, limestone, mica, clay, salt, silver, talc, and zinc. The climate is subtropical, arid, warm, and dry, with an average minimum temperature of 29° in January and an average high temperature of 94° in July. The growing season averages 230 days a year, and the average annual precipitation is less than ten inches. Less than 1 percent of the land in Hudspeth County is considered prime farmland.