Floors 31, 32, 33 and 34 of the hotel will be renumbered 56, 57, 58 and 59, said Brian Ahern, a spokesman for MGM Resorts International, which owns the Mandalay Bay.
Stephen Paddock, a 64-year-old retiree, fired on the Route 91 Harvest festival on October 1 from a suite he had rented on the 32nd floor of the Mandalay Bay before taking his own life.
The tower, which is 43 stories tall, had already used an unconventional floor-numbering system before the massacre in which the top four floors were listed as 60-63.
Paddock's shooting spree, which also wounded nearly 500 people, ranks as the deadliest mass shooting in modern US history.
Haig, 55, has said none of the surplus military ammunition was fired during the killing spree, and that he had no inkling of any criminal intent by Paddock.
No motive for the massacre has ever been established.