“An Officer and a Spy” made its debut at the festival on Friday.
Polanski, 86, who has lived outside of the United States and avoided extradition since pleading guilty in 1977 to unlawful sex with a minor, did not attend the festival. His wife, the French actress Emmanuelle Seigner, who appears in the film, accepted the prize on his behalf.
Polanski has come under fire for drawing parallels between his legal ordeal and that of Dreyfus prior.
Dreyfus, a Jewish officer in the French military, was sentenced in 1894 to life in prison for allegedly passing secrets to the German Embassy in Paris. He was imprisoned for five years before being exonerated when evidence of the prosecution’s partially anti-Semitic motives was discovered.
Raised in Poland, Polanski survived Krakow’s Jewish ghetto as a child and, after launching his film career in Poland after the war, moved to the United States in 1968.
“Joker,” which delves into the backstory of the comic book villain and Batman nemesis, won the Golden Lion for best film.