Beyonce Dances at Jay Z and Justin Timberlake's Concert After-Party

Beyonce posted pictures of herself dancing and partying at Jay Z and Justin Timberlake Legends of the Summer concert after-party. Credit: Courtesy Beyonce

When Beyonce's off mommy duty, she knows how to party! The 31-year-old singer and mom to 18-month-old daughter Blue Ivy posted new photos on Instagram Tuesday, July 30, of herself dancing and letting loose at husband Jay Z and Justin Timberlake's Legends of the Summer concert after-party.

In one collage of pictures, Beyonce shows off close-ups of her head-to-toe Givenchy ensemble: a striped tank top and leggings. In another photo collage, Beyonce dances with Jay Z, 43, and friends while holding a beverage and flashes the camera a fierce, snarling expression for the camera.

Following Jay Z and Timberlake's performance at the Rose Bowl in Pasadena, Calif. on Sunday, July 28, the duo held a star-studded after-party in a private room backstage. A source tells Us Weekly that in addition to Beyonce, Timberlake's wife Jessica Biel was in attendance, as well as Jessica Alba and husband Cash Warren, Kelly Rowland, Demi Lovato, Wilmer Valderrama, Rashida Jones, Zoe Kravitz and other A-listers.

The insider tells Us that Beyonce "danced the entire time" and the guests enjoyed DJ Cassidy and DJ Jus Ske's mix of "late '80s, R&B and dance" music. In addition to enjoying a D'usse cognac open bar, partygoers snacked on mini burgers and other finger food.

"The party went there until 3 a.m.," the source says. "It was just nothing but fun."