Argonia is a city in Sumner County, Kansas, United States. As of the 2010 census, the city population was 501.
Argonia is located at 37°15′55″N 97°45′58″W / 37.26528°N 97.76611°W / 37.26528; -97.76611 (37.265299, -97.766123). According to the United States Census Bureau, the city has a total area of 0.6 square miles (1.7 km²), all of it land.
As of the census of 2000, there were 534 people, 225 households, and 146 families residing in the city. The population density was 818.4 people per square mile (317.2/km²). There were 255 housing units at an average density of 390.8 per square mile (151.5/km²). The racial makeup of the city was 96.82% White, 0.37% African American, 0.37% from other races, and 2.43% from two or more races. Hispanic or Latino of any race were 0.19% of the population.