Perry was highly anticipated at the event, which will take place Wednesday night. However, she announced her absence on Twitter, without citing a specific reason.
“Unfortunately I will not be able to attend,” she wrote on the social network. “I want to thank u all for voting for me, fingers crossed! #KATYCATS.”
Katy is nominated in six categories, including Best Female Artist and Best Song for her collaboration with Kanye West on ET.
Last week, reports stated that Russell Brand was removed from the list of guests at the event in order to avoid an unfortunate encounter between the former spouses.
Since the announcement of her divorce on December 30, the 27-year-old remained silent until Sunday when she addressed the breakup on Twitter.
“Concerning the gossip, I want to be clear that NO ONE speaks for me. Not a blog, magazine, ‘close sources’ or my family,” she wrote.
“I am so grateful for all the love and support I’ve had from people around the world,” Katy added. “You guys have made my heart happy again.”