Decatur is a town in Green County, Wisconsin, United States.

As of the census[2] of 2000, there were 1,688 people, 587 households, and 501 families residing in the town.

There were 645 housing units at an average density of 18.9 per square mile (7.3/km2).

There were 587 households, out of which 40.5% had children under the age of 18 living with them, 76.0% were married couples living together, 5.3% had a female householder with no husband present, and 14.5% were non-families.

10.7% of all households were made up of individuals, and 4.1% had someone living alone who was 65 years of age or older.