Cayuga is a city in Sargent County, North Dakota, United States.

According to the United States Census Bureau, the city has a total area of 0.99 square miles (2.56 km2), all land.

There were 26 housing units at an average density of 26.3 per square mile (10.2/km2).

There were 32 housing units at an average density of 32.4 per square mile (12.5/km2).

46.2% of all households were made up of individuals, and 23.1% had someone living alone who was 65 years of age or older.

There were no families and 8.6% of the population living below the poverty line, including no under eighteen and 25.0% of those over 64.