The Oratorio del Santissimo Crocifisso or the Oratory of the Most Holy Crucifix is a building in central Rome, Italy.

Connected to the nearby church of San Marcello al Corso, it houses the Crucifix of San Marcello and served as a chapel and meeting place for the Archconfraternity of the Most Holy Crucifix (Arciconfraternita del Santissimo Crocifisso in Urbe) devoted to the image.

The structure was built by Giacomo Della Porta in 1568, near the church of San Marcello.

The confraternity was composed of some of the richest men in Rome, including the cardinals Ranuccio and Alessandro Farnese, nephews of the Pope.

It employed Giovanni de' Vecchi, Cesare Nebbia, Niccolò Circignani, and Cristoforo Roncalli.