Martin (Lakota: pažóla otȟúŋwahe;[6] "Knoll City") is a city and the county seat of Bennett County, South Dakota, United States.

[9] The city was named for Eben Martin, a U.S. Representative from South Dakota.

[10] According to the United States Census Bureau, the city has a total area of 0.53 square miles (1.37 km2), all land.

South Dakota Highway 73 runs north into the town and makes a T-intersection with U.S. 18.

There were 467 housing units at an average density of 881.1 per square mile (340.2/km2).

32.7% of all households were made up of individuals, and 15.7% had someone living alone who was 65 years of age or older.

35.6% of all households were made up of individuals, and 17.6% had someone living alone who was 65 years of age or older.