Countryside is a city in Cook County, Illinois, United States. The population was 5,991 at the 2000 census.
According to the United States Census Bureau, the city has a total area of 2.7 square miles (7.0 km²), all of it land.
As of the census of 2000, there were 5,991 people, 2,661 households, and 1,604 families residing in the city. The population density was 2,226.7 people per square mile (859.9/km²). There were 2,818 housing units at an average density of 1,047.4 per square mile (404.5/km²). The racial makeup of the city was 92.29% White, 2.15% African American, 0.10% Native American, 1.55% Asian, 2.19% from other races, and 1.72% from two or more races. Hispanic or Latino of any race were 6.84% of the population.