It will mark the first time he has taken part in the event since 2006, when he finished in a tie for 59th competing as an amateur.
The event, co-sanctioned by OneAsia and the PGA Tour of Australasia, will also witness a home appearance for Australia's world number four Scott, who became the first golfer from his country to triumph at Augusta National earlier this year.
"It's been a few years since I last competed in an Australian Open," McIlroy, who also played in the Australian Masters in 2007 in Melbourne and finished tied for 15th, said in a statement from the organisers.
"I am very much looking forward to returning to Royal Sydney."
Former world number one McIlroy, who has endured a patchy season, showed glimpses of a return to form at last week's U.S. PGA Championship at Oak Hill, where he finished in a tie for eighth after flirting with a missed cut in his second round.
(Reporting by Sudipto Ganguly in Mumbai; Editing by John O'Brien)
