Unionville is a city in Appanoose County, Iowa, United States.

[3] Unionville claims to be the oldest settlement in Appanoose County; the first settles arrived in 1843 and the first school was built in 1846.

[8] According to the United States Census Bureau, the city has a total area of 0.75 square miles (1.94 km2), all land.

There were 49 housing units at an average density of 64.8 per square mile (25.0/km2).

There were 60 housing units at an average density of 80.0 per square mile (30.9/km2).

36.7% of all households were made up of individuals, and 12.3% had someone living alone who was 65 years of age or older.

There were 68 housing units at an average density of 91.3 per square mile (35.3/km2).

24.0% of all households were made up of individuals, and 12.0% had someone living alone who was 65 years of age or older.

There were 9.1% of families and 11.3% of the population living below the poverty line, including 22.2% of under eighteens and none of those over 64.