Designer Karl Lagerfeld has called Adele "a little too fat" during an interview with a French newspaper.
The 78-year-old made the remark while he was guest editor of the Paris edition of free paper Metro.
He was being asked about Lana Del Rey but claimed he preferred Florence Welch and Adele, who he said had "a beautiful face and divine voice".
Adele has not commented on the interview but her fans have gone on Twitter to voice their anger.
One said: "Karl... Adele is fat... So are lots of other women... Now, get over yourself and go back to doing what you're good at!"
Another added: "Who cares what Karl Lagerfeld says about Adele? When you're as talented as her wearing Chanel isn't going to change anything!"
The controversial designer also said Britain's Royal Family was "totally unnecessary, but pleasant".
He said the monarchy was "good for the tourists".
"It brings a lot of money in," he said. "Why not have the monarchy? People can dream about it."
In a string of insults he also called Russian men "ugly" and said Greeks and Italians had "disgusting habits".
Asked about the debt crisis in Greece, he said: "Greece needs to work on a cleaner image. It's a big problem, as they have this reputation of being so corrupt.
"You can't be sure the money will go where it's supposed to go.
"Nobody wants Greece to disappear, but they have really disgusting habits. Italy as well."
Karl Lagerfeld, who was born in the German city of Hamburg, is head designer and creative director for French fashion house Chanel.
He also has his own label and works with Italian firm Fendi.
In the Metro interview, Lagerfeld also talked about the Queen ahead of her Diamond Jubilee.
"She looks a little bit like her grandmother - a more smiley version.
"In terms of what she wears, she's come into herself a little bit more - whatever that is."
The designer has caused controversy in the past.
He has been criticised for his use of fur on the catwalk and said that supermodel Heidi Klum was "insignificant" outside Germany.