Osceola is a city in Clarke County, Iowa, United States. The population was 4,929 at the 2010 census. It is the county seat of Clarke County.
Osceola is located at 41°2′3″N 93°46′6″W (41.034179, -93.768354), at the junction of Interstate 35 and U.S. Routes 34 and 69. It lies 35 miles (56 km) north of the Missouri border, and approximately 40 miles south of Des Moines.
According to the United States Census Bureau, the city has a total area of 6.68 square miles (17.30 km2), of which 6.48 square miles (16.78 km2) is land and 0.20 square miles (0.52 km2) is water.
Osceola was named after a Seminole Indian leader of the same name. Osceola is an anglicised form of Asiyahola: assi, from a ceremonial yaupon holly tea or "black drink" and yaholi, the name of a Creek god intoned when the drink was served.
The Masonic Building stands on the public square in Osceola. Built in 1872, this Italianate building was used by Osceola Lodge No. 77 of the Ancient Free & Accepted Masons, and the main floor was a bank and hardware store. This building was placed on the Iowa Historic Preservation Alliance’s Most Endangered list due to its poor repair and lack of preservation plan.