Leonardo DiCaprio spent a wild weekend in Las Vegas, partying up a storm with scantily clad showgirls, swilling booze and smoking pot in a jam-packed nightclub.

“It was debauchery and excess for three straight days,” boasted a friend of the “Titanic” heartthrob.

Leo came to town for the Palms Casino Resort’s extravagant one-year anniversary party, and to celebrate his 28th birthday.

He and his friends arrived on Thursday, November 14, and checked into the “high roller” suites on the 20th floor.

“Leo was invited by Palms owner George Maloof, a source told The ENQUIRER.

“George provided Leo with airfare and his $7,000-a-night room was free of charge.”

Leo began his stay with a private dinner party at the N9NE Steak House in the Palms before a blowout Thursday night birthday bash in his hotel suite.

He even sent for the hot showgirls from the Aladdin’s racy new show called “X.”

“The Aladdin sent over a half-dozen girls to party with Leo and his friends and provide entertainment,” said an insider.

“The place was crawling with half-naked women. Leo was flirting with all of them.”

The following night Leo and his pals hit the swanky nightclub Rain, located in the Palms.

“Leo was smoking pot right out in the open, and it didn’t look like he cared who saw him,” an eyewitness told The ENQUIRER.

“Afterward, Leo and his friends retired to his room and partied until the early morning hours.”

The actor was back at Rain on Saturday night for a private party.

Bikini-clad women were splashed out on buffet tables as Leo, Tobey Maguire and other friends dined before retiring to the club’s VIP section.

Leo mingled with a raucous group of women in the VIP section, letting loose as singer Macy Gray and the rap band Onyx surprised the crowd with an unannounced performance.

But once again the real party was back in Leo’s hotel suite, where alcohol was free-flowing and “the main bedroom was one big cloud of marijuana smoke,” said an eyewitness.

Leo’s wild weekend finally came to an end on Sunday when he checked out and returned to L.A.

Said a pal: “I hope he remembers how much fun he had!”