The Netflix movie, which will see Ana play a fictionalised version of the legendary actress, has been in development since 2010, but fans will have to wait a bit longer to see it.
According to Variety, the film is expected to drop next year but a specific release date has not been confirmed.
The movie is to be directed by Andrew Dominik, from Joyce Carol Oates' historical novel "Blonde" that chronicles the inner life of Marilyn Monroe.
Adrien Brody and Bobby Cannavale are also set to star in the film, as Monroe's former husbands Arthur Miller and Joe DiMaggio respectively. Julianne Nicholson will play the actress' mother Gladys Pearl Baker.
In February 2020, de Armas described her casting as Monroe - who died in 1962 aged 36 - as "ground-breaking."
She said, "Playing Marilyn was ground-breaking. A Cuban playing Marilyn Monroe. I wanted it so badly."
Ana - who stars in upcoming James Bond blockbuster "No Time to Die" - only had to audition for director Dominik once before earning the lead role, but still had to convince the producers of her suitability for the part.
"The producers. The money people. I always have people I needed to convince," she explained. "But I knew I could do it. I have never worked more closely with a director than I worked with Andrew."
"Yes, I have had collaborative relationships, but to get phone calls at midnight because he has an idea and he can't sleep and all of a sudden you can't sleep for the same reason."