Festival director Thierry Fremaux says Amazon's presence is good news because its SVOD (streaming video on demand) service releases its films in cinemas before they are streamed online.
The film industry prefers having these so-called "release windows" - usually three months - when they can show the film exclusively. Netflix releases its films at the same time in cinemas and online.
"They have Woody Allen but also some foreign films, so it's good news because thanks to them these films will be distributed," he said.
The festival will kick off with Woody Allen's 'Cafe Society', one of five Amazon films selected in Cannes. Three of them have been picked for the main competition.
Nicolas Winding Refn's 'The Neon Demon', Jim Jarmusch's 'Paterson' and 'Gimme Danger' and Park Chan-wook's 'The Handmaiden' are also Amazon's.
"The presence of Amazon is not significant (just) for the Cannes film festival, it's significant for the whole industry of cinema," Fremaux said.
"I think it's good news, it's money, a new kind of money. Having Amazon buying four, five films is a very good sign showing cinema is alive."
This year, Netflix and Amazon bought a combined total of 12 films at the Sundance film festival and the Venice film festival screened Netflix's 'Beasts of No Nation' last year.
© Thomson Reuters 2016