The British retro-soul singer was to perform at the Sept. 9 event in Las Vegas, but her U.S. record label, Universal Republic Records, said Wednesday that all U.S. appearances have been canceled "in a continued effort to support Amy Winehouse's well-being."
It is the latest setback for the gifted but troubled 23-year-old. Last week, she was photographed with her husband, Blake Fielder-Civil, bloodied and bruised after an apparent fight in a London hotel.
The gossip Web site perezhilton.com has said it received text messages from Winehouse denying Fielder-Civil was responsible for her injuries, saying she cut herself after he found her about to do drugs.
She canceled a series of British concerts and postponed a tour of the U.S. and Canada after British media reported that she was in and out of rehab recently.
Winehouse made her U.S. debut this year with the acclaimed album "Back to Black," but her tabloid troubles have often overshadowed her talent. She has spoken openly about her past battles with drugs and her penchant for alcohol and marijuana. Her hit single "Rehab" is an autobiographical tale of her resistance to being pushed to go to rehab.