Teigen caught the All of Me singer from behind as he was attempting to change the channel on a TV in their hotel suite and posted it on Twitter.
She then hit her Instagram account and urged followers to check out her man's bare rear - and that landed her in trouble with the nudity police, who thought the shot was a dig at the site's naked photo policy.
She tells U.S. news show Extra, "They actually wrote my agency at one point; they were like, 'Please stop posting this'."
Teigen, who has often landed in trouble for posting saucy shots of herself online, insists her husband didn't object to sharing the photo of him naked, adding, "He didn't know I was taking it but he knew I was tweeting it... He got full approval.
"It's such a good butt, how do you not post that? It's so good!"