The Manueline style Chapter Room, built by Diogo Boitaca (1507-1513) was the place where the friars met in assembly to make the key decisions of conventual life. The tiles that decorate the room are also from the 16th century.

Heading the Chapter Room is the beautiful chapel of São Teotónio, Mannerist architecture, designed by Tomé Velho (dating from around 1588), topped by a large arch, and was built to receive the Tomb of São Teotónio. In this space there are images of Saint Teotónio and the 4 evangelists (Saint Matthew, Saint Mark, Saint John and Saint Luke). The chapel functions, in reality, as a kind of main chapel of the Chapter Room, “sacralizing” the two separate spaces, nevertheless united by the great triumphal arch, built in the 17th century.

There are also two more tombs in this Chapel, that of D. Telo (one of the founders of the monastery who died in 1136 and transferred to this location in 1630) and that of D. João Teotónio (second Prior of the monastery, who died in 1181, and who he was the nephew of S. Teotónio, he was also transferred to this chapel in 1630). It is still possible to see the benches with their respective backs, where the friars sat to discuss and make important decisions. The paintings that we find here and adorn the room are by the Augustinian friars.

In this Room, as in other places in the monastery, a formal agreement is also created between the roof and the paving slab, communicating a kind of cosmic harmony between heaven and earth.