South Heart is a city in Stark County, North Dakota, United States.

There were 129 housing units at an average density of 135.8 per square mile (52.4/km2).

28.1% of all households were made up of individuals, and 11.6% had someone living alone who was 65 years of age or older.

The racial makeup of the city was 98.70% White, 0.33% African American, and 0.98% from two or more races.

21.3% of all households were made up of individuals, and 6.5% had someone living alone who was 65 years of age or older.

About 8.0% of families and 9.4% of the population were below the poverty line, including 7.9% of those under the age of eighteen and 18.2% of those 65 or over.