Maria Antónia Siza (1940–1973), was a Portuguese artist who left an estate with more than 3,000 works, including drawings, gouache paintings, and embroidery, but only exhibited once before her early death.

Her father, Alberto Leite, was an office worker, art lover and painter in his spare time, while her mother, Maria Luísa Marinho, was the daughter of the owner of a textile company.

[1][2] While receiving praise from her teachers, Siza's style did not follow the established consensus and, whilst her contemporaries were mainly producing abstract art, she was not prepared to compromise to achieve wider acceptance.

Her style has been described as containing elements of figurativism, expressionism and surrealism and she produced works in gouache, charcoal, India ink, watercolours, oil painting, and embroidery, as well as engravings.

[1] A selection of the works of Siza was published in 2002 by Edições Asa in association with a new exhibition at Cooperativa Árvore in Porto.