Osterdock is a city located in Clayton County, Iowa, United States.

[5] According to the United States Census Bureau, the city has a total area of 0.46 square miles (1.19 km2), all land.

There were 19 housing units at an average density of 48.1 per square mile (18.6/km2).

Hispanic or Latino persons of any race comprised 4.7% of the population.

There were 23 housing units at an average density of 50.0 per square mile (19.3/km2).

26.1% of all households were made up of individuals, and 8.7% had someone living alone who was 65 years of age or older.

There were 21 housing units at an average density of 46.2 per square mile (17.8/km2).

23.8% of all households were made up of individuals, and 9.5% had someone living alone who was 65 years of age or older.

Out of the total population, none of those under the age of 18 and 36.4% of those 65 and older were living below the poverty line.