The sexy seniors -- whose combined age is 142 -- turned up at the Beverly Hills bash looking more fabulous than the two fortysomethings.
Fitness queen Fonda, 72, epitomized Hollywood royalty in a black sequined strapless gown accessorized by long white gloves and a sparkly choker, reports the Daily Mail.
Meanwhile, 70-year-old '60s sexbomb Welch proved she can still throw a curve by donning a slinky, purple off-the-shoulder body-hugging dress with a plunging neckline.
Welch's form-fitting number showed nary a crease, much like her face.
The actress reportedly told Oprah Winfrey her oh-so-smooth skin is the result of three hours of prep time -- not to mention diet, yoga, and exercise.
Fonda, however, has fessed up to having her neck, chin, and eyes fixed, but attributes her fine figure to regular exercise.
In fact, the Daily Mail reports that on Oct. 24 the Oscar winner proved she could still bust a move at Maria Shriver's Women's Conference in Long Beach, Calif., where she walked "Glee" star Jane Lynch -- as well as the crowd -- through one of her workouts.
Plus, weigh in on the thigh-baring bridal look J.Lo wore to the event.
In related news, read Joan Collins's take on plastic surgery and stars Jennifer Aniston and Angelina Jolie.