Dona Maria Francisca Isabel of Savoy (French: Marie Françoise Élisabeth; 21 June 1646[1] – 27 December 1683) was Queen of Portugal during her marriage to King Dom Afonso VI from 2 August 1666 to 24 March 1668 and, as the wife of Afonso's brother King Dom Peter II, from 12 September 1683 until her death in December that year.

On 28 March 1668, she married the King's brother Infante Dom Peter, Duke of Beja, who was appointed prince regent the same year due to Afonso's perceived incompetence.

Maria Francisca was born in Paris as the younger daughter of Charles Amadeus of Savoy, Duke of Nemours, and his wife, Élisabeth de Bourbon-Vendôme.

[9][10] Afonso appointed Castelo Melhor his secret notary (escrivão da puridade), a position in which the Count was able to exercise the functions of chief minister.

[13] Louis XIV welcomed the idea of a Portuguese marriage, aiming to increase France's influence in Portugal and weaken Spain by prolonging the Restoration War.

Charles II of England, who greatly desired peace between Spain and Portugal, opposed the match but Louis XIV persuaded him to agree by providing him with the unpaid portion of Catherine's dowry.

[22] Afonso’s brother Peter led a growing faction at court that opposed the excessive power Castelo Melhor wielded over Portuguese affairs.

[21][25] In September 1667, Peter orchestrated a palace coup de’tat that dismissed Melhor and forced Afonso to relinquish his power.

[36] Louis XIV had supported the coup against Afonso VI with the expectation that it would increase French influence at court through Maria Francisca.

Maria Francisca was initially interred at the Convent of the Francesinhas, but her remains were transferred to the Pantheon of the House of Braganza at the Monastery of São Vicente de Fora in 1912.