In an Instagram post on Tuesday, Washington first thanked the industry mag for showcasing her so prominently.
"I always celebrate it when a respected publication invites me to grace their pages. It's an honor. And a privilege. And ADWEEK is no exception."
Then Washington addressed the matter of her appearance on the cover, for which she models a black and white striped dress before a bold graphic background.
"Look, I'm no stranger to Photoshopping. It happens a lot. In a way, we have become a society of picture adjusters - who doesn't love a filter?!? And I don't always take these adjustments to task but I have had the opportunity to address the impact of my altered image in the past and I think it's a valuable conversation."
The AdWeek cover was a bridge too far for the "Django Unchained" actress.
"Yesterday, however, I just felt weary. It felt strange to look at a picture of myself that is so different from what I look like when I look in the mirror. It's an unfortunate feeling."
Washington's fans agreed that the cover didn't do her justice
"This is upsetting. This picture looks nothing like you...you're 100000000 times more beautiful than this picture. Why can't people just calm down on the photoshop and appreciate REAL beauty," dandc.designs commented under the photo.
Some took the magazine to task on its Instagram page.
"Well I thought it was Kerry Washington but it was photoshopped so bad that I don't know who that woman on the cover actually is," said an Instagrammer who goes by simply_shanetta91.
The magazine responded to the hubbub in a statement.
"Kerry Washington is a class act. We are honored to have her grace our pages. To clarify, we made minimal adjustments, solely for the cover's design needs. We meant no disrespect, quite the opposite. We are glad she is enthusiastic about the piece and appreciate her honest comments," Editorial Director James Cooper said.
Washington isn't the first celeb to accuse a publication of altering their image.
Lena Dunham criticized a Spanish newspaper
in March for what she saw as an unrealistic depiction of her body within its pages. The paper, El Pais, denied Photoshopping Dunham but admitted it could have been done before the image was sold to the publication.
Heavy use of photo editing software has become a big issue in recent years, with numerous celebrities and others railing against the practice of digitally thinning bodies and making other changes that can drastically alter a person's appearance to a sometimes absurd extent.
Critics have accused magazines of using the technology to peddle an unrealistic -- and often unattainable -- standard of beauty.
In October, singer and actress Zendaya called out Modeliste for heavily altering images of her and posted the original images side by side with the retouched versions.
"These are the things that make women self conscious, that create the unrealistic ideals of beauty that we have," she wrote.
Washington chose her words carefully when criticizing the cover on Tuesday, saying she's proud of the article and happy with the other images inside the mag.
"Grab this week's ADWEEK. Read it. I hope you enjoy it," she said. "And thank you for being patient with me while I figured out how to post this in a way that felt both celebratory and honest.