St. Donatus is a city in Jackson County, Iowa, United States.

[4] St. Donatus is known for its status as a Luxembourgish village, with historic architecture and views along U.S. Route 52.

It is the home of a historic Catholic church, which is dedicated to Saint Donatus of Muenstereifel, the town's namesake.

[5] According to the United States Census Bureau, the city has a total area of 0.37 square miles (0.96 km2), all land.

There were 62 housing units at an average density of 165.8 per square mile (64.0/km2).

There were 57 housing units at an average density of 153.6 per square mile (59.3/km2).

22.2% of all households were made up of individuals, and 11.1% had someone living alone who was 65 years of age or older.

18.9% of all households were made up of individuals, and 7.5% had someone living alone who was 65 years of age or older.

There were none of the families and 0.7% of the population living below the poverty line, including no under eighteens and 5.3% of those over 64.