Gary is a city in Deuel County, South Dakota, United States. The population was 227 at the 2010 census.
Gary is located at 44°47′35″N 96°27′27″W / 44.79306°N 96.4575°W / 44.79306; -96.4575 (44.793178, -96.457569).
According to the United States Census Bureau, the city has a total area of 0.7 square miles (1.8 km²), all of it land. The West Branch of the Lac qui Parle River flows through the city as an intermittent stream near its headwaters.