The whole choir, with its gothic vaults, was painted by Jean Baleison around 1460.
He has probably used the in tempera technique.

The « Transitus Mariae », that is to say the lasts moments of the Virgin's life, is illustrated on the walls :
- « the Second Annunciation », which is the annunciation of her approaching death.
- Saint John's visit to Mary
- The Dormition of the Virgin
- The transport of the Virgin's body

The Assumption and the additional scenes are represented on the apse's wall.

On the vaults, the four Evangelists are represented.
The Doctors of the Church are situated on the inner surface of the gothic arch, establishing a communication between the choir and the nave.

The triumphal arch and the lateral walls of the nave were painted by Jean Canavesio and finished on the 12th of October of 1492, according to an inscription situated on one of the panels of the decoration.
This second painter used the in fresco technique.

The triumphal arch bears eleven panels illustrating the Virgin's life and Christ's Childhood.

On the lateral walls, twenty six panels illustrate the cycle of the Passion.
They are disposed on two superposed registers, except for the Crucifixion which occupies the whole height of the wall.