At age 46, Jennifer Lopez is hotter than ever!

The actress, pop singer  and mother of 7-year-old twins turned heads at her birthday party at the 1OAK Southampton nightclub in Southampton City, New York on Saturday.

J.Lo sported a sexy black cut-out knee-length Bao Tranchi dress with cap sleeves, a scoop neckline and sheer cut-out panels that showed off plenty of cleavage and her signature curves. She paired the look with black strappy sandals.

Lopez turned 46 on Friday and posted that day a throwback photo of herself as a child at a previous celebration.

Jennifer Lopez

Jerritt Clark/Getty Images

Jennifer Lopez

Jerritt Clark/Getty Images

At her 46th birthday party, she was accompanied by her beau Casper Smart, 28, who sported a cornflower blue blazer over a white, crisp, button-down shirt and black pants.

"J.Lo and Casper never left each other's side," a source told E! News. "They held hands when they walked in. Looked very much together."

Jennifer Lopez, Casper Smart

IGGI / Splash News

The two later posed for photos inside the party.

Jennifer Lopez, Casper Smart

Matteo Prandoni/BFA.com

Lopez appeared to be in great spirits and was seen hanging by the DJ booth.

Jennifer Lopez

Jerritt Clark/Getty Images

She also hung out with rappers French Montana, 30, and Fat Joe, 44, as well as Mexican singer Thalía, 43.

The Bronx is out tonight ?? @jlo @fatjoe #Thalia ??

A photo posted by French Montana (@frenchmontana) on

"What a special girl," Fat Joe said on Instagram. "Never changed on me ever. I'm blessed to have her in my life."

—Additional reporting by Sara Kitnick

We and our partners use cookies on this site to improve our service, perform analytics, personalize advertising, measure advertising performance, and remember website preferences. By using the site, you consent to these cookies. For more information on cookies including how to manage your consent visit our Cookie Policy.