The Polk County portion of Mitchellville is part of the Des Moines–West Des Moines Metropolitan Statistical Area, while the Jasper County portion is part of the Newton Micropolitan Statistical Area.
The Iowa Correctional Institution for Women is located in Mitchellville.
As of the census of 2000, there were 1,715 people, 650 households, and 455 families residing in the city. The population density was 746.4 people per square mile (287.9/km²). There were 675 housing units at an average density of 293.8/sq mi (113.3/km²). The racial makeup of the city was 97.49% White, 0.29% African American, 0.12% Native American, 0.70% Asian, 0.41% from other races, and 0.99% from two or more races. Hispanic or Latino of any race were 1.34% of the population.
There were 650 households out of which 39.4% had children under the age of 18 living with them, 55.7% were married couples living together, 10.8% had a female householder with no husband present, and 30.0% were non-families. 25.5% of all households were made up of individuals and 10.8% had someone living alone who was 65 years of age or older. The average household size was 2.55 and the average family size was 3.09.
In the city the population was spread out with 28.9% under the age of 18, 7.9% from 18 to 24, 29.5% from 25 to 44, 20.0% from 45 to 64, and 13.6% who were 65 years of age or older. The median age was 35 years. For every 100 females there were 95.6 males. For every 100 females age 18 and over, there were 87.0 males.
The median income for a household in the city was $45,250, and the median income for a family was $52,113. Males had a median income of $34,327 versus $26,202 for females. The per capita income for the city was $18,572. About 4.3% of families and 4.6% of the population were below the poverty line, including 4.9% of those under age 18 and 7.5% of those age 65 or over.