El Llano is a municipality in the Mexican state of Aguascalientes. It stands at .
As of 2010, the municipality had a total population of 18,828, up from 17,115 in 2005.
The municipality had 244 localities, the largest of which (with 2010 populations in parentheses) were: the municipal seat of Palo Alto (5,399), classified as urban, and Los Conos (1,108), Ojo de Agua de Crucitas (1,078), and Santa Rosa (El Huizache) (1,050), classified as rural.