"We're delighted to confirm that Pete Wentz and Ashlee Simpson were married this evening in front of family and close friends," said the spokesperson.
Simpson, 23, and Wentz, 28, exchanged vows in front of 150 guests at her parents' Los Angeles area home.
Dad Joe Simpson performed the non-denominational ceremony, while sister Jessica served as maid of honor. Wentz's English bulldog, Hemingway, was the ring-bearer. Guests included Jessica's boyfriend, Dallas Cowboys quarterback Tony Romo, Nicole Richie and Joel Madden.