Glendale Heights is a village in DuPage County, Illinois, United States. The population was 34,208 at the 2010 census.
Glendale Heights was a small farming area served by the Glen Ellyn post office up until the 1950s, with a population of just 104 in 1959. Midland Enterprises ran by Charles and Harold Reskin started building houses in Glendale Heights in 1958. The Reskins bought two farms on Glen Ellyn Road north of North Avenue. Houses were first built on Glen Ellyn Road and Larry Lane near Fullerton Avenue. On June 16, 1959, a petition was filed and on July 13, the village became incorporated. The first election was held later on that summer on August 2.
The town was originally named Glendale as it was between Glen Ellyn and Bloomingdale, but after a conflict arose with the small town of Glendale in Southern Illinois, the city decided in March 1960 to add the term Heights, in reference to its different topographies, a difference of about 100 feet because of its location straddling the Valparaiso Morraine, thus becoming Glendale Heights.
Glendale Heights is located at 41°55′13″N 88°4′44″W (41.920228, −88.078918).
According to the 2010 census, Glendale Heights has a total area of 5.51 square miles (14.27 km2), of which 5.37 square miles (13.91 km2) (or 97.46%) is land and 0.14 square miles (0.36 km2) (or 2.54%) is water.
At the 2000 census there were 31,765 people, 10,791 households, and 7,596 families living in the village. The population density was 5,877.8 people per square mile (2,271.2/km²).