SIMON COWELL is hoping he gets PRETTY before he gets old in his bizarre quest to stay “ageless”.

YOUTH-obsessed Simon Cowell will do almost anything to beat Father Time – including undergoing a cutting edge cosmetic pro­cedure and sleeping in a hyperbaric chamber like Michael Jackson!

Sources say the “X Fac­tor” judge believes that the chamber’s pure oxygen helped him heal after a re­cently having a neck-lift to make him look younger than his 53 years.

“Simon will be the FIRST person to tell you that he doesn’t mind getting older,” revealed an insider.

“But the truth is he’ll try anything that keeps him looking like he’s in his late 30s or early 40s.”

The former “American Idol” judge gets regular Botox injec­tions, and as The E N Q U I R E R has reported, he’s had placenta protein “masks” to erase wrinkles.

In one of his latest bids to turn back time, Simon had his saggy “turkey neck” tightened in a noninvasive procedure by a Beverly Hills plastic surgeon in October, said the source.

The neck-lift was like­ly done with the new Fractora Firm device, said Michigan-based plastic sur­geon Dr. Anthony Youn, who has not treated Cow­ell. The device uses radio frequency energy to create tissue-firming collagen under the skin.

After the treatment, “Si­mon brought a technician  with a portable hyperbaric cham­ber into his Beverly Hills home,” said the insider. “He spent about an hour a day in the chamber for a period of weeks. He usually fell asleep, and when he got out, he said he felt like a new man.

“Simon believes that being in the chamber helped suppress the swelling from his surgery as well as bloating from his drinking and years-long smoking habit.”

As The ENQUIRER reported in a blockbuster world exclusive in September 1986, Michael Jackson slept in a hyperbaric chamber as part of his plan to live to 150.

The late King of Pop’s cham­ber was the size and shape of a casket with a clear top, but Simon is using a more modern plastic sleeping bag-like device, said the source.

“Simon feels as if he’s found the Fountain of Youth, and he’s considering investing in a more permanent machine,” said the source.

“He’s convinced that he can stop the ‘Aging Factor’ and look great for many years to come.”