Pierron is a village in Bond and Madison counties, Illinois, United States. The population was 600 as of the 2010 census.
The first post office was established at Pierron in 1870. Pierron was laid out as a village in 1871, and named for its founder Jacques Pierron. Pierron was incorporated as a village in 1893.
Pierron is located at 38°46′44″N 89°33′34″W (38.778767, -89.559306).
According to the 2010 census, Pierron has a total area of 0.84 square miles (2.18 km2), all land.
As of the census of 2000, there were 653 people, 251 households, and 175 families residing in the village. The population density was 767.6 people per square mile (296.6/km²). There were 268 housing units at an average density of 315.0 per square mile (121.7/km²). The racial makeup of the village was 96.63% White, 0.15% African American, 0.15% Native American, 0.15% Asian, 0.61% from other races, and 2.30% from two or more races. Hispanic or Latino of any race were 0.92% of the population.
There were 251 households out of which 35.1% had children under the age of 18 living with them, 55.4% were married couples living together, 10.0% had a female householder with no husband present, and 29.9% were non-families.