The Kankakee-Bradley Metropolitan Statistical Area includes all of Kankakee County. The county is also part of the larger Chicago–Naperville–Michigan City, IL-IN-WI Combined Statistical Area.
As of the census of 2000, there were 103,833 people, 38,182 households, and 26,765 families residing in the county. The population density was 153 people per square mile (59/km²). There were 40,610 housing units at an average density of 60 per square mile (23/km²). The racial makeup of the county was 79.89% White, 15.47% Black or African American, 0.18% Native American, 0.68% Asian, 0.02% Pacific Islander, 2.38% from other races, and 1.38% from two or more races. 4.78% of the population were Hispanic or Latino of any race. 21.3% were of German, 9.9% Irish, 8.7% French, 6.6% American and 5.4% English ancestry according to Census 2000. 94.1% spoke English and 4.3% Spanish as their first language.
There were 38,182 households out of which 34.40% had children under the age of 18 living with them, 52.80% were married couples living together, 13.10% had a female householder with no husband present, and 29.90% were non-families. 24.90% of all households were made up of individuals and 10.40% had someone living alone who was 65 years of age or older. The average household size was 2.61 and the average family size was 3.12.
In the county the population was spread out with 27.10% under the age of 18, 9.70% from 18 to 24, 28.20% from 25 to 44, 22.00% from 45 to 64, and 13.10% who were 65 years of age or older. The median age was 35 years. For every 100 females there were 95.60 males. For every 100 females age 18 and over, there were 91.90 males.
The median income for a household in the county was $41,532, and the median income for a family was $48,975. Males had a median income of $37,776 versus $25,287 for females. The per capita income for the county was $19,055. About 8.70% of families and 11.40% of the population were below the poverty line, including 15.60% of those under age 18 and 7.20% of those age 65 or over.