Quinn is a town in Pennington County, South Dakota, United States.

[7] The town is the home of the Badlands Observatory, located in the former community hospital, built in 1950.

[10] Quinn Methodist Church is on the National Register of Historic Places.

According to the United States Census Bureau, the town has a total area of 1.16 square miles (3.00 km2), all land.

30.4% of all households were made up of individuals, and 21.7% had someone living alone who was 65 years of age or older.

38.9% of all households were made up of individuals, and 22.2% had someone living alone who was 65 years of age or older.