George of Trebizond (Greek: Γεώργιος Τραπεζούντιος; 1395–1472 or 1473) was a Greek philosopher, scholar and humanist.
He was born on the Greek island of Crete (then a Venetian colony known as the Kingdom of Candia), and derived his surname Trapezuntius from the fact that his ancestors were from the Byzantine Greek Trapezuntine Empire.
At what period he went to Italy is not certain; according to some accounts he was summoned to Venice about 1430 to act as amanuensis to Francesco Barbaro, who appears to have already made his acquaintance; according to others he did not visit Italy till the time of the Council of Florence (1438–1439).
He learned Latin from Vittorino da Feltre, and made such rapid progress that in three years he was able to teach Latin literature and rhetoric. His reputation as a teacher and a translator of Aristotle was very great, and he was selected as secretary by Pope Nicholas V, an ardent Aristotelian. The needless bitterness of his attacks upon Plato (in the Comparatio Aristotelis et Platonis), which drew forth a powerful response from Basilios Bessarion, and the manifestly hurried and inaccurate character of his translations of Plato, Aristotle and other classical authors, combined to ruin his fame as a scholar, and to endanger his position as a teacher of philosophy. (Pope Pius II was among the critics of George's translations.) The indignation against George on account of his first-named work was so great that he would probably have been compelled to leave Italy had not Alfonso V of Aragon given him protection at the court of Naples.