Since she posted it, the image has been liked over 80,000 times.
People seemed to love the fact that celebs, just like us, can be guilty of letting things slide a bit in the beauty stakes.
"You never try to hide anything - you're the most honest and straight forward!" said one commenter.
"Thank you for this! More people need to understand that 'perfection' is an illusion and that true beauty is underneath. Have always loved you, love you more now," said another.
Website Hello Giggles also sang Barrymore's praises: "We can't even imagine what it must feel like to be under constant public scrutiny, and it takes a lot of courage to just put yourself out there as you truly are instead of attempting to create an illusion of perfection," Toria Sheffield wrote.
Other commenters praised the fact that the actor's forehead appeared to be free of injectables.
Barrymore, who has her own makeup line called Flower, spoke to the New York Times earlier this year about her simple beauty routine.
"I would say 90 per cent of my life, I wear zero makeup," she said.
The actor posted the pic to promote the upcoming season of her Netflix series Santa Clarita Diet.
