The 50-year-old Australian actress and Urban, also 50, attended the 2018 Academy of Country Music Awards at MGM Grand Garden Arena in Las Vegas.
Kidman, who turned heads in a gold gown with a high neck and bishop sleeves, was all smiles as she posed for photos by Urban's side.
"It's been a magical year," Urban told Entertainment Tonight. "Ripcord was a magical album, and it's great to be at the ACMs, always."
Urban was nominated for five awards, and won Vocal Event of the Year for his single "The Fighter" featuring Carrie Underwood. He also performed his song "Coming Home" with Julia Michaels.
"Backstage at the #ACMawards with my hubby and @juliamichaels #ComingHome #GraffitiU," Kidman captioned a photo on Instagram with the pair.
"The Fighter" and "Coming Home" appear on Urban's albums Ripcord and Graffiti U, respectively. Graffiti U will debut in its entirety April 27.
Kidman, meanwhile, will reprise Celeste Wright in Season 2 of the HBO series Big Little Lies. She will also appear in a number of upcoming films, including Aquaman with Jason Momoa and Boy Erased with Lucas Hedges.