It was the first time the tennis icon has made a red carpet appearance since the birth of her daughter, Alexis Olympia Ohanian Jr., in September.
The four-time Olympic gold medalist complemented the gold embroidery on her dress with lots of golden accessories.
Williams presented the Supernova Award to her friend, Gigi Hadid, at the awards show.
“Gigi, you are one of the few people on this planet I would leave my baby for ― for one night ― but for you, it shows how much you mean to me. And I want you to imagine the effect you have on the world,” Williams said to Hadid, according to People.
“Since I’ve known Gigi Hadid since she was a kid, she’s always been a woman with goals,” she added. “Not only beautiful on the outside but totally stunning most importantly on the inside. She understands in order to be the best you have to think like you are the best. You have to work the hardest and you have to make sacrifices.”