There are strong indigenous customs. Its name in Nahuatl language means "place of four Izalcos "; by tradition, it was founded by four families from the nearby town of Izalco. It is famous for its wicker and tule handcrafts. Tule is processed in two different varieties: the water kind, brought from the Pacific coast, and the dark one used for making "petates" (floor mats). Nahuizalco is also famous for its night market. The streets are lit only by candles and the products made of wicker and tule are sold until 10pm.
The colonial church was seriously damaged during the earthquake of 2001 and subsequently restored. The church honors John the Baptist every June 20 - 25.