The Casa de Santa Maria (House of Saint Mary) was once a luxurious private residence in Cascais, Lisbon District, Portugal.

In the late 19th century, Jorge O'Neil, an aristocrat with many business connections, purchased some land near the Santa Marta area of Cascais.

In the case of Santa Maria, he was instructed to disregard the popular styles of the time and design the house using only materials found within Portugal.

Lino, a major collector and art lover, purchased, from an old chapel in Frielas, a set of 17th century Azulejo tiles and a wooden oil-painted ceiling, which has been attributed to António de Oliveira Bernardes.

On the ground floor the walls of the rooms are covered with polychrome blue and yellow painted tiles, originally from the Marvila Convent in Lisbon.