Lucas County Courthouse Square Historic District is a nationally recognized historic district located in Chariton, Iowa, United States. It was listed on the National Register of Historic Places in 2014. At the time of its nomination the district consisted of 76 resources, including 56 contributing buildings, one contributing site, one contributing structure, three contributing objects, 14 noncontributing buildings, one noncontributing structure, and one noncontributing object. The historic district covers the city's central business district in the original town plat. The buildings were either built or remodeled between 1867 and 1963, and range from one- to three-stories in height. They all have brick exteriors. Of the older buildings, the Commercial Italianate style is dominant.