The Ghost star, 59, posed on a paddle board as she floated on crystal clear turquoise waters.
Pairing her triangle string bikini with a set of dark sunglasses, the actress declared she was in "paradise".
Demi has collaborated with Andie Swim to create a set of bikinis that she’s proud of and loves to wear.
Recently, she spilled to Vogue that her favourite style is a "simple triangle bikini", and she wanted to create a "sexy and sweet" swimwear range.
“I think it exudes confidence to know that you don’t need to show a lot of skin to be sexy,” she told the publication.
“[You have] the option to feel covered, but to not have it be matronly. It still feels flirty, sexy and fun.”
The Indecent Proposal star was praised by fans who said she was "beautiful".
“Obviously found the fountain of youth! Absolutely stunningly beautiful, as always!” gushed a fan.
“You looked good 40 years ago, you looked good 20 years ago, and you look even better now in 2022. Timeless beauty and a great actor to boot,” another declared.
“I want Demi Moore’s body! How does she do it?” asked a fan.
“I’d say she’s just as hot now as she was back in the day, but the truth is I think she’s even hotter,” a fourth chimed in.
Demi's pink bikini
This comes after the star donned a bright pink bikini onboard a luxury yacht in Greece.
Fans declared she was "ageless" and her famous family members commented on her post.
“You’re such a hottie mama, my God,” wrote her daughter Rumer Willis.
“And it looks so good on you!” added Emma Heming Willis, who is currently married to Demi’s ex Bruce Willis.
Her fans were also quick to heap praise on the actress, with one saying she had "legs for days".
“The years don’t pass you by Demi…I don’t know what you do to keep fit, but it’s working,” a fan wrote.
“I hope I look like this at your age,” another chimed in.
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