The singer and actress shared their outfits from the celebration on Instagram including matching white T-shirts with the phrase "Make America Skate Again," a play on President Trump's campaign slogan "Make America Great Again."
"Sign the petition now!" Biel captioned the photo.
Timberlake shared a short, slow-motion video of himself roller skating while donning an American flag jacket, denim shorts, patriotic socks, an American flag fanny pack and a yellow hat.
"When you throw a roller skating Bday party for your wife but you can't figure out how to wear your hat," Timberlake captioned the clip.
Biel also posted a photo of herself skating inside an empty roller rink underneath a disco ball while wearing a pair of bell-bottoms. "This is what birthday dreams are made of. Thank you, my love, for throwing me the most epic jam skate party ever. My inner Xanadu was fully realized. I love you to the moon and back. And then back again," she wrote.
Biel's former 7th Heaven costar Beverley Mitchell and her husband Michael Cameron attended the event.
Earlier on Instagram, Timberlake paid tribute to Biel writing, "You make me laugh. You make me smile. You make me LOVE. You make me want to be BETTER."