The former child star, whose hits include "Baby One More Time" and "Toxic," will perform 50 shows a year starting on Dec. 27. Tickets for the shows go on sale on Tuesday.
"I love it here. The energy here is really, really good," Spears said in an interview from Las Vegas on Tuesday on ABC's "Good Morning America."
"I am definitely going to do the greatest hits but I am going to have to put my new material in it to keep it fresh," she said.
The announcement ended speculation that Spears, 31, would follow in the footsteps of other top-selling artists such as Canada's Celine Dion and Britain's Elton John, who had long-term contracts in the gambling mecca.
Terms of Spears' two-year deal have not been released. Dion's three-year deal was said to be worth $100 million.
Caesars Entertainment Corp, which owns Planet Hollywood and resorts and casinos, said in February that it was in talks with Spears about a headlining residency at its resort.
Spears hit the big time in the 1990s, and was one of the biggest pop stars of the 2000s. But her early fame was followed by troubled years during which she lost custody of her two young sons and spent time in rehab.
She was a judge on the popular singing competition show, "The X Factor," in 2012 but left after one season.
Twenty-eight buses carried 1,300 fans — and one Sam Champion — into the middle of nowhere to watch the “Oops!… I Did It Again” songstress make her highly-touted announcement Tuesday on "Good Morning America."
In the pre-recorded conversation, Spears also weighed in on Miley Cyrus’ MTV VMA performance:
“I think anytime you’re doing a performance that is that memorable, you’re going to have criticism,” Spears said. “I think she’s doing her thing. She’s being herself — so I give props to her.”
The pop star also told Champion that her first kiss was at age 13 with ex-boyfriend Justin Timberlake.
Spears arrived live in the desert via helicopter, while below her scores of fans flipped some cards over from below forming photos of the pop star. The mother of two admitted to getting sick while hovering above.
From the comfort of the earth, Spears announced that her new untitled album will be released Dec. 3.