is a city in DeKalb County, Indiana, United States. The population was 12,074 at the 2000 census. Founded in 1836 by Wesley Park (1811-1868), the city is the county seat of DeKalb County.
According to the United States Census Bureau, the city has a total area of 6.7 square miles (17.2 km²), all of it land.
Most of Auburn is located in Union civil township. Portions of Jackson, Keyser and Grant civil townships are also within the city limits.