Libertyville is a village in Lake County, Illinois, United States, and a northern suburb of Chicago. It is located 5 miles (8 km) west of Lake Michigan along the Des Plaines River. The 2020 census population was 20,579. It is part of Libertyville Township, which includes the village, neighboring Green Oaks, and portions of Vernon Hills, Mundelein, unincorporated Waukegan and Lake Forest, and part of Knollwood CDP. Libertyville neighbors these communities as well as Gurnee to the north and Grayslake to the northwest. Libertyville is about 40 miles north of the Chicago Loop and is part of the United States Census Bureau's Chicago combined statistical area (CSA).

Lake County is situated in the northeastern corner of the U.S. state of Illinois, along the shores of Lake Michigan. As of the 2020 census, it has a population of 714,342, making it the third-most populous county in Illinois. Its county seat is Waukegan, the tenth-largest city in Illinois. The county is primarily suburban, with some urban areas and some rural areas. Due to its location, immediately north of Cook County, Lake County is one of the collar counties of the Chicago metropolitan area. Its northern boundary is the Wisconsin state line.