Green Oaks is a village in Libertyville Township, Lake County, Illinois, United States. The population was 3,866 at the 2010 census.
Green Oaks is located at 42°17′20″N 87°54′41″W (42.289106, -87.911499).
According to the 2010 census, Green Oaks has a total area of 4.123 square miles (10.68 km2), of which 4.02 square miles (10.41 km2) (or 97.5%) is land and 0.103 square miles (0.27 km2) (or 2.5%) is water.
At the 2000 census, there were 3,572 people, 1,079 households and 977 families living in the village. The population density was 892.0 per square mile (344.8/km2). There were 1,109 housing units at an average density of 276.9 per square mile (107.0/km2). The racial makeup of the village was 90.85% White, 1.74% African American, 0.14% Native American, 5.46% Asian, 0.42% from other races, and 1.40% from two or more races. Hispanic or Latino of any race were 2.63% of the population.
There were 1,079 households, of which 52.5% had children under the age of 18 living with them, 86.2% were married couples living together, 3.4% had a female householder with no husband present, and 9.4% were non-families. 7.6% of all households were made up of individuals, and 2.2% had someone living alone who was 65 years of age or older. The average household size was 3.26 and the average family size was 3.44.