Chihuahua (Spanish pronunciation: [tʃiˈwawa]), officially Free and Sovereign State of Chihuahua (Spanish: Estado Libre y Soberano de Chihuahua), is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. Its capital city is Chihuahua.

It is located in Northwestern Mexico. It is bordered by the states of Sonora to the west, Sinaloa to the southwest, Durango to the south, and Coahuila to the east. To the north and northeast, it has a long line with the U.S.–Mexico border adjacent to the U.S. states of New Mexico and Texas.

Chihuahua is the largest state in Mexico by area, with a mainland area of 247,455 square kilometres (95,543 sq mi), it is slightly larger than the United Kingdom. It is consequently known under the nickname El Estado Grande ("The Big State").

Although Chihuahua is primarily identified with the Chihuahuan Desert for namesake, it has more forests than any other state in Mexico. Due to its variant climate the state has a large variety of fauna and flora. The state is mostly characterized by rugged mountainous terrain and wide river valleys. The Sierra Madre Occidental mountain range, an extension of the Rocky Mountains, dominates the state's terrain and is home to the state's greatest attraction, Las Barrancas del Cobre, or Copper Canyon, a canyon system larger and deeper than the Grand Canyon. On the slope of the Sierra Madre Occidental mountains (around the regions of Casas Grandes, Cuauhtémoc and Parral), there are vast prairies of short yellow grass, the source of the bulk of the state's agricultural production. Most of the inhabitants live along the Rio Grande Valley and the Conchos River Valley.