Lostant is a village founded 1861, in LaSalle County, Illinois, United States. The population was 486 at the 2000 census. It is part of the Ottawa–Streator Micropolitan Statistical Area.
Lostant is located at 41°8′32″N 89°3′41″W / 41.14222°N 89.06139°W / 41.14222; -89.06139 (41.142127, -89.061384).
According to the United States Census Bureau, the village has a total area of 0.4 square miles (1.0 km²), all of it land.