The organ was built between 1689 and 1691 by Josep Boscà and Serinyena and essentially remains in its original conception. The metal pipe has been repaired by Gerhard Grenzing since 1984 because it lost it during the Civil War. The fact that it has preserved so many constituent elements in addition to the box gives it sufficient entity to consider it the oldest organ in Catalonia. When in 1689 he agreed to the construction of the organ, it was agreed that he should do so in accordance with what was in the church of the convent of Sant Domènec in Girona, the first one that someone has attributed to his hands, although it seems more likely that it was Bartomeu Triay.

When the doors reveal the face of the main organ, the left one shows the worship of the shepherds and the right, the worship of the magicians; when the doors are closed, Jesus is taught with a disciple and Adam and Eve, respectively. If the curtain of the cadireta is unrolled, a recurrent scene is seen in the doors and curtains of the organs: the Annunciation.