She shared a photo of the cover of the New York Times, which featured Katy at the fashion event.
But it was a second photo on the image of the newspaper that upset many followers.
The cover showed an image of a French policeman who had been set on fire during recent protests in Paris.
The page also has two stories about Donald Trump and the New York Times has taken an anti-Trump stance since his election in November 2016.
Katy famously campaigned on behalf of Hillary Clinton during last year's presidential race and has said that some of her new music has been inspired by global politics.
Katy shared the photo with the caption "All the news that's fit to print."
But many followers considered the post insensitive.
"Disgusting. Are you really so selfish Katy? Is your dress really so important that you think this is at all acceptable? I hope that police officer makes it home to his family," wrote one user.
"There's obviously much more worthy news than yours. You should have cropped the pic or whatever if you really cant help yourself. Very insensitive of you to be honest," wrote another.
"Just lost a fan. Someone is on fire but yes let's adore the dress," said a follower.
But other fans said that the point of the post had been missed.
"She is being facetious. Her point, although executed poorly, is that her dress should NOT be fit to print on the front page," wrote a fan.
"In other words, her reaction to this newspaper page is exactly the reaction you're all having."
The photo comments also prompted a discussion among international Katy Perry fans about the current French presidential race and the two candidates, Marine Le Pen and Emmanuel Macron.
So far, representatives for Katy Perry have not commented.