Wilson's memoir, which is named Rebel Rising, is set to feature a chapter where she talks about "a massive a**hole" that she had previously worked with in Hollywood.
However, this person's identity has remained unknown, until on Monday last, when Wilson posted on Instagram that the person she was referring to was Ali G and Borat star Sacha Baron Cohen. The pair had worked together on his 2016 spy action comedy, The Brothers Grimsby.
In a post which has since been deleted, Rebel Wilson had alleged that Baron Cohen's team had been "trying to stop press coming out about my book".
"But the book WILL come out, and you will all know the truth", she said, before adding that she would "not be bullied or silenced by high-priced lawyers or PR crisis managers".
Wilson then went on to name and shame Baron Cohen, "The 'a**hole' I was talking about in one chapter of my book is: Sacha Baron Cohen".
Following this, a representative of Sacha Baron Cohen released this statement.
"While we appreciate the importance of speaking out, these demonstrably false claims are directly contradicted by extensive detailed evidence, including contemporaneous documents, film footage, and eyewitness accounts from those present before, during and after the production of 'The Brothers Grimsby'", they said.
The film itself saw Sacha Baron Cohen star as the main character Nobby, an alcoholic football hooligan turned elite spy, who was married to Wilson's character Dawn Grobham, who was the mother to their 11 children.
The Brothers Grimsby also starred Penelope Cruz, Mark Strong, and Isla Fisher, Baron Cohen's off screen wife.
Rebel Wilson is renowned for her role as Fat Amy in musical comedy film, Pitch Perfect, having previously burst onto the scene as character Brynn in the 2011 comedy movie, Bridesmaids.
Rebel Rising is due to be published next month.
