Oglesby is a city in LaSalle County, Illinois, United States. The population was 3,791 at the 2010 census. It is part of the Ottawa–Streator Micropolitan Statistical Area.
Oglesby Lincoln, Oglesby Washington, Holy Family, and Illinois Valley Community College are located in Oglesby.
Oglesby is located at 41°17′48″N 89°3′58″W / 41.29667°N 89.06611°W / 41.29667; -89.06611 (41.296762, -89.066074).