The cute couple were spotted snuggling up in the stands at the Melbourne, Australia, match between Naomi Osaka of Japan and Karolina Pliskova of the Czech Republic.
Urban, 51, gave his wife a sweet kiss on the forehead, while the Oscar winning actress was seen putting her arm around his neck as they watched the action on the court.
Kidman, 51, sported a white floral lace ensemble, while the "Fighter" crooner rocked a navy blue polka dot buttondown shrit and black pants.
Kidman posted a selfie with her hubby on Instagram, writing, "I love tennis! Thank you for having us #AusOpen."
Earlier this month, Kidman revealed that Urban made some seriously romantic overtures to convince her to marry him when they first began dating in 2005.
"It was my [38th] birthday, and he stood outside with gardenias at 5 a.m. on my stoop in New York," she gushed. "That is when I went, 'This is the man I hope I get to marry.'"
They tied the knot in 2006 and now share daughters Sunday Rose, 10, and Faith Margaret, 8.