Santissimo Crocifisso Olmo, Religious monument in Mazzarino, Italy.

Santissimo Crocifisso Olmo is a church in Mazzarino with three naves divided by four cylindrical columns with Doric capitals, each supporting round arches. The interior has a barrel vault with stucco decorations added in 1886 by the Fantaguzzi brothers. Seven altars have inlaid polychrome marble mensas and Sicilian paintings from the 16th and 17th centuries.

The church's origins trace to the 10th–11th century, after the Norman reconquest of Sicily, when the Aleramici founded a Siculo-Norman church dedicated to the Madonna dell'Itria. In 1756 Filippo Bivona, a Mazzarino-born merchant, restored the interior and remade the altars in marble. The Confraternita del Santissimo Crocifisso dell'Olmo was established here in 1881 to carry the heavy fercolo in the second-Sunday-of-May procession.

The Confraternita del Santissimo Crocifisso dell'Olmo, also called della Vara, was established in this church in 1881 to carry the heavy fercolo in procession on the second Sunday of May. The crucifix was the town's patron until 1832, when the Madonna del Mazzaro became patron and it was proclaimed co-patron.

The church sits on Via Gallo north of Santa Maria della Neve and opens daily to visitors. During May and December celebrations, extended visiting hours are available to accommodate larger gatherings.

Local legend tells of thieves who attempted to steal the crucifix but abandoned their plan when their elm staff mysteriously grew into a full tree. This tale lives on in community memory and inspired the church's name.