Greene County is part of the Springfield, Missouri, Metropolitan Statistical Area.
As of the census of 2000, there were 240,391 people, 97,859 households, and 61,846 families residing in the county. The population density was 356 people per square mile (138/km²). There were 104,517 housing units at an average density of 155 per square mile (60/km²). The racial makeup of the county was 93.54% White, 2.26% Black or African American, 0.66% Native American, 1.13% Asian, 0.06% Pacific Islander, 0.67% from other races, and 1.68% from two or more races. 1.84% of the population were Hispanic or Latino of any race.
There were 97,859 households out of which 28.30% had children under the age of 18 living with them, 50.00% were married couples living together, 9.80% had a female householder with no husband present, and 36.80% were non-families. 29.10% of all households were made up of individuals and 9.70% had someone living alone who was 65 years of age or older. The average household size was 2.34 and the average family size was 2.89.
In the county the population was spread out with 22.30% under the age of 18, 13.80% from 18 to 24, 28.60% from 25 to 44, 21.80% from 45 to 64, and 13.60% who were 65 years of age or older. The median age was 35 years. For every 100 females there were 94.40 males. For every 100 females age 18 and over, there were 91.20 males.
The median income for a household in the county was $34,157, and the median income for a family was $42,613. Males had a median income of $30,672 versus $21,987 for females. The per capita income for the county was $19,185. About 7.60% of families and 12.10% of the population were below the poverty line, including 13.60% of those under age 18 and 7.50% of those age 65 or over.