The Life Ball, taking place on Saturday evening, is the biggest annual charity event in Europe supporting people with HIV or AIDS.
Desperate Housewives star Marcia Cross and singer Courtney Love flew in alongside pop star Kesha.
Actor Billy Zane said he was "looking forward to adding my voice to the good cause." He and Marcia Cross will be doing a reading as part of the Red Ribbon Celebration Concert this evening at the Burgtheater.
Life Ball organizer Gery Keszler said the plane journey had been lots of fun but that he hadn’t had enough sleep.
Transgender model Carmen Carrera, pictured on this year’s controversial poster for the event, said she was surprised over the debate caused by David LaChapelle’s design, which features Carrera nude with both male and female genitalia – and has attracted many complaints and a lawsuit.
"It's my first controversy, and if someone has felt offended, then I’m sorry," Carrera told reporters.
"But I think it's time to show that there is more than just male or female in this world. This is my message,” she added.
The far right Freedom Party is suing the Life Ball over the campaign, accusing the posters of being pornographic. People have been tearing the posters down, vandalising them, and painting over them.
Meanwhile actress Lindsay Lohan will fly to Vienna from London. Ricky Martin, Bill Clinton, Leona Lewis and Conchita Wurst have also confirmed their attendance.
The Life Ball will be broadcast live on ORF television, and The Local Austria will also be covering the event.