Greensburg is a town in and the parish seat of St. Helena Parish, Louisiana, United States. The population was 631 at the 2000 census. It is part of the Baton Rouge Metropolitan Statistical Area. Greensburg is one of the oldest towns in Louisiana.
During the American Civil War, Union General Albert L. Lee left from Baton Rouge with a division of cavalry on October 5, 1864, and raided Greensburg, where his men destroyed a tannery containing two thousand sides of leather. He also seized a large supply of quinine.
Greensburg is located at 30°49′41″N 90°40′9″W / 30.82806°N 90.66917°W / 30.82806; -90.66917 (30.827953, -90.669302).