Lenzburg is a village in St. Clair County, Illinois, USA.

[4] As of the census[6] of 2000, there were 577 people, 217 households, and 169 families residing in the village.

There were 235 housing units at an average density of 190.3 per square mile (73.5/km2).

The racial makeup of the village was 99.13% White, 0.17% Native American, 0.17% Asian, and 0.52% from two or more races.

17.5% of all households were made up of individuals, and 8.3% had someone living alone who was 65 years of age or older.