Union is a town in Pierce County, Wisconsin, United States.

The unincorporated community of Ono is located partially in the town.

As of the census[2] of 2000, there were 618 people, 212 households, and 168 families residing in the town.

There were 215 housing units at an average density of 6.2 per square mile (2.4/km2).

17.0% of all households were made up of individuals, and 5.7% had someone living alone who was 65 years of age or older.