The American rapper walked hand-in-hand with Kardashian at the launch of "Cruel Summer" on Wednesday night.
The couple didn't stop to talk to media but some of the cast revealed what it was like to work on the art project.
Described as an "immersive seven-screen experience," ''Cruel Summer" is a love story set in the Middle East and inspired by West's new "G.O.O.D" album.
Lebanese actress Razan Jammal says West is "an amazing person" to work with.
"To be honest I was really, really surprised, he's so professional. A little shy, very calm on set, very hard working - I loved working with him," she said.
The film installation will now be open to the public for two days.
Elsewhere in the French Riviera city, the Cannes Film Festival continues through May 27.
