Prince Pedro Gastão of Orléans-Braganza (born Pierre-d’Alcantara Gaston Jean Marie Philippe Laurent Hubert d’Orléans et Bragance ; in Portuguese, Pedro de Alcântara Gastão João Maria Filipe Lourenço Humberto Miguel Gabriel Rafael Gonzaga de Orléans e Bragança e Dobrzensky de Dobrzenicz) (19 February 1913 – 27 December 2007)  was one of two claimants to the Brazilian throne and head of the Petrópolis branch of the Brazilian Imperial House.

Prince Pedro Gastão was the son of Prince Pedro de Alcântara of Orléans-Braganza and his wife Countess Elisabeth Dobržensky de Dobrženicz. He was born in Eu, France. He spent his youth in Europe and at his family’s Parisian home in the Boulogne sur Seine suburb: “I have very good memories of my grandparents…In exile in France I was always brought up thinking of Brazil not France or Portugal.”

A few years before his death Pedro Gastão’s father Prince Pedro de Alcântara told a Brazilian newspaper:

“My resignation was not valid for many reasons: besides, it was not a hereditary resignation.”
Following the death of his father supported by Infante Alfonso, Duke of Calabria and Infante Juan, Count of Barcelona he declared himself head of the Imperial Family of Brazil. His position was supported by Francisco Morato the professor of the faculty of Law at the University of São Paulo who concluded the resignation of Pedro Gastão’s father was not a valid legal or monarchical act[citation needed]. Professor Paulo Napoleão Nogueira da Silva in the 1990s published a report saying that the resignation of his father was invalid under all possible aspects of Brazilian Law.

He represented a rival claim to that of his cousin’s son, Prince Luiz of Orléans-Braganza, to be the heir of the deposed Emperor Pedro II of Brazil, despite the renunciation signed by his father in 1908 when he married, without dynastic approval, a Bohemian noblewoman.

Pedro Gastão died aged 94 on 27 December 2007.

He married Princess Maria de la Esperanza of Bourbon-Two Sicilies (1914–2005), a daughter of Prince Carlos of the Two Sicilies and Princess Louise of Orléans, on 18 December 1944 in Seville, Spain, and had six children:

Prince Pedro Carlos of Orléans-Braganza (born 31 October 1945), succeeded to his father’s claim as Emperor on 27 December 2007.
Princess Maria da Gloria of Orléans-Braganza (born 13 December 1946), former Crown Princess of Yugoslavia.
Prince Alfonso Duarte of Orléans-Braganza (born 25 April 1948)
Prince Manuel Álvaro of Orléans-Braganza (born 17 June 1949)
Princess Cristina Maria of Orléans-Braganza (born 16 October 1950)
Prince Francisco Humberto of Orléans-Braganza (born 9 December 1956)