Osawatomie is a city in Miami County, Kansas, United States, 61 miles (98 km) southwest of Kansas City. The population was 4,645 at the 2000 census. It derives its name from two streams near by, the Osage and Potawatomie. In 1900, 4,101 people lived in Osawatomie; in 1910, 4,046. Osawatomie was chartered in 1883 and in 1890 became a second-class city. The commission form of government was adopted in 1914.