The 28-year-old star, who is pregnant with her second child with husband Ryan Reynolds, posted a split picture of images taken from the front and back when she was at the premiere of her new movie "Cafe Society" at Cannes last week.
Quickly, the actress came under fire from commenters who accused her of being privileged, using black women and culture as a "punchline".
"Another day, another rich white woman using WOC's bodies as a punchline and commodity. As if Blake Lively wasn't the worst already," one user wrote on Twitter.