Menominee is part of the Marinette, WI–MI Micropolitan Statistical Area.
As of the census of 2000, there were 9,131 people, 4,063 households, and 2,441 families residing in the city. The population density was 1,763.2 per square mile (680.6/km²). There were 4,393 housing units at an average density of 848.3/sq mi (327.4/km²). The racial makeup of the city was 97.35% White, 0.14% African American, 0.82% Native American, 0.32% Asian, 0.27% from other races, and 1.10% from two or more races. Hispanic or Latino of any race were 1.12% of the population. 31.6% were of German, 9.3% French, 8.7% Swedish, 8.7% Polish, 7.2% Irish and 6.7% French Canadian ancestry according to Census 2000.
There were 4,063 households out of which 27.9% had children under the age of 18 living with them, 43.6% were married couples living together, 12.4% had a female householder with no husband present, and 39.9% were non-families. 35.3% of all households were made up of individuals and 15.0% had someone living alone who was 65 years of age or older. The average household size was 2.22 and the average family size was 2.86.
In the city the population was spread out with 23.9% under the age of 18, 9.4% from 18 to 24, 25.8% from 25 to 44, 22.8% from 45 to 64, and 18.2% who were 65 years of age or older. The median age was 39 years. For every 100 females there were 92.8 males. For every 100 females age 18 and over, there were 90.4 males.
The median income for a household in the city was $30,523, and the median income for a family was $38,867. Males had a median income of $32,850 versus $22,145 for females. The per capita income for the city was $17,500. About 9.9% of families and 13.3% of the population were below the poverty line, including 18.2% of those under age 18 and 11.9% of those age 65 or over.