Wearing a red sequin minidress and white cowboy boots, the iconic singer sang her hit singles Man! I Feel Like A Woman and You're Still The One with Harry, who appeared ecstatic to have her on stage with him, dancing around the star as she sang.
WATCH: Shania Twain makes surprise Coachella appearance
"Coachella, are you ready to have some fun tonight?" the 28-year-old asked the packed crowd after singing his hit song Golden, only for the band to play the opening chords and Shania appeared from below the stage.
"Make some noise for Shania Twain!" he said, adding: "Now, I have to tell you in the car with my mother as a child, this lady taught me to sing. She also told me that men are trash, but the memories you gave me with my mother, I’ll be forever grateful."
"I am so honored and thrilled to be here,” Shania added, admitting she was "starstruck" to be on stage with Harry.
"No, really, I’m a fan of you, of course. I realize that when I was writing this song, you were just a little kid. It’s kind of a dream and very surreal to be sitting here right now to sing this song with you. I think I’m just in love and this song is all about love. So let’s just sing about love."
Shania and Harry stunned in their outfit
Harry kicked off his 80-minute set with new song As It Was, and joked: "It’s big in here, innit?"
"For the next 80-or-something minutes, our job is to entertain you. I promise you we’ll do our absolute very best," he continued.
"You also have one job — that is to have much fun as you possibly can. I want you to be whoever it is you always wanted to be in this field tonight."
He also debuted two new songs - Boyfriends and Late Night Talking.
"Who in the audience has ever had a boyfriend? Who in the audience has never had a boyfriend? To boyfriends everywhere, [expletive] you,” he joked.
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