Hagen Township was named for an early Norwegian settler.

As of the census[1] of 2000, there were 153 people, 56 households, and 45 families residing in the township.

There were 72 housing units at an average density of 2.2 per square mile (0.85/km2).

There were 56 households, out of which 30.4% had children under the age of 18 living with them, 75.0% were married couples living together, 1.8% had a female householder with no husband present, and 19.6% were non-families.

14.3% of all households were made up of individuals, and 3.6% had someone living alone who was 65 years of age or older.