Giovanni Francesco Commendone (17 March 1523 – 26 December 1584) was an Italian Cardinal and papal nuncio.
Commendone was born at Venice. After an education in the humanities and in jurisprudence at the University of Padua, he came to Rome in 1550. The ambassador of Venice presented him to Pope Julius III, who appointed him one of his secretaries.
After successfully performing various papal missions of minor importance, he accompanied Cardinal Legate Girolamo Dandino to the Netherlands, whence Pope Julius III sent him in 1553 on an important mission to Queen Mary Tudor, who had just succeeded Edward VI on the English throne. He was to treat with the new queen concerning the restoration of the Catholic faith in England.
Accompanied by Penning, a servant and confidant of Cardinal Reginald Pole, Commendone arrived in London on 8 August 1553. Though Mary Tudor was a loyal Catholic, she was surrounded at court by numerous opponents of papal authority, who made it difficult for Commendone to obtain a secret interview with her. By chance he met John Lee, a relation of the Duke of Norfolk and an attendant at court, with whom he had become acquainted in Italy, and Lee succeeded in arranging the interview. Mary received Commendone kindly, and expressed her desire to restore the Catholic Faith and to acknowledge the spiritual authority of the pope, but considered it prudent to act slowly on account of her powerful opponents, Commendone hastened to Rome, arriving there on 11 September, and informed the pope of the news, at the same time handing him a personal letter from the queen.
Commendone continued to hold the office of papal secretary under Pope Paul IV, who esteemed him very highly and in return for his services appointed him bishop of Kephalonia and Zacynthus in 1555. In the summer of 1556 he accompanied Cardinal Legate Scipione Rebiba on a papal mission to the Netherlands, to the courts of Charles V, Holy Roman Emperor and King Philip II of Spain, the consort of Queen Mary of England. Commendone had received instructions to remain as nuncio at the court of Philip, but he was recalled to Rome soon after his arrival in the Netherlands. On 16 September of the same year the pope sent him as extraordinary legate to the Governments of Urbino, Ferrara, Venice, and Parma in order to obtain help against the Spanish troops who were occupying the Campagna and threatening Rome.