Masonville is a city in Delaware County, Iowa, United States.

[3] The city is located on the western border between Delaware and Buchanan counties.

[5] According to the United States Census Bureau, the city has a total area of 0.33 square miles (0.85 km2), all land.

There were 51 housing units at an average density of 155.9 per square mile (60.2/km2).

Hispanic or Latino persons of any race comprised 1.0% of the population.

There were 57 housing units at an average density of 172.7 per square mile (66.7/km2).

27.3% of all households were made up of individuals, and 3.6% had someone living alone who was 65 years of age or older.

26.5% of all households were made up of individuals, and 18.4% had someone living alone who was 65 years of age or older.

There were 3.0% of families and 5.1% of the population living below the poverty line, including no under eighteens and 15.4% of those over 64.