Humaitá is a town in southern Paraguay, lying on the River Paraguay. It is best known for its role as the major Paraguayan stronghold in the War of the Triple Alliance, when it was home to up to 24,000 troops from 1866 until its fall in August 1868. Until March of that year, it was the de facto home of the Paraguayan government.

Parts of the fortifications, including large earthworks, are still visible. The other main attraction is the remains of a Jesuit church, largely destroyed in the battles.