[5] As of the census[1] of 2000, there were 463 people, 202 households, and 139 families residing in the township.

There were 202 households, out of which 20.3% had children under the age of 18 living with them, 60.4% were married couples living together, 4.0% had a female householder with no husband present, and 30.7% were non-families.

27.7% of all households were made up of individuals, and 13.9% had someone living alone who was 65 years of age or older.

Males had a median income of $28,250 versus $18,125 for females.

Millen Township is served entirely by Alcona Community Schools.