Leon is a city in Nicaragua, Central America, located at 12.43°North, 86.89°West. In full the legal name of the city, granted in Spanish Colonial times, is Santiago de los Caballeros de León, but this is little used. It is the capital of Nicaragua's León Department. As of 2003 the city had an estimated population of about 198,000 people in which 2% are Americans and Canadians.

Leon is situated on the León River, some 50 miles northwest of Managua, and some 11 miles north of the Pacific Ocean coast. Although less populous than Managua, León has long been the intellectual center of the nation, with the University founded here in 1813. León is also an important industrial and commercial center for Nicaragua.

The first city of León in Nicaragua was established in 1523 by Francisco Fernandez de Cordoba about 20 miles east of the present site; this old León was severely damaged by an eruption of the volcano Momotombo, and so the city was moved to its present location, which had been a Native American town named Subtiaba'.

Leon has fine examples of Spanish Colonial architecture, including the grand Cathedral of San Pedro, built from 1706 to 1740, with two towers added in 1746 and 1779.

When Nicaragua withdrew from the United Provinces of Central America in 1839, León became the capital of the new nation of Nicaragua. For some years the capital shifted back and forth between León and Granada, Nicaragua, with Liberal regemes preferring León and Conservative ones Granada, until as a compromise Managua was agreed upon to be the permanent capital in 1858.