The superstar songstress was invited down to the famous attraction in New York yesterday (13 February) to switch on the sparkly lights and while there, she also treated visitors to an intimate performance of her romantic new single 'You're Mine (Eternal)'.
Joining Mariah at the Empire State were three couples who won a competition to get married on top of the NYC building in time for Valentine's Day.
But they were a little upstaged by the famous singer, as she decided to wear white too in keeping with the wedding theme of the night. And of course she went all out with glamorous accessories as well!
Mariah donned a figure-hugging white frock, which flattered her curves and added a pair of long white gloves.
She completed her look with a pair of dazzling diamond earrings and styled her hair into sexy waves.
Later in the evening, the mum-of-two changed into a gorgeous, long-sleeved red gown for her performance. A perfect colour for Valentine's!
It definitely seemed like Mariah was embracing all the love in the air last night, even though husband Nick Cannon wasn't by her side.
She and Nick are known for being a super romantic couple and regularly shower one another with affection, posting cute photos as proof on their respective Instagram accounts.
The head-over-heels pair got married in 2008 in the Bahamas and they have two children together: Monroe and Moroccan.
Last April, Mariah and Nick proved just how much marriage means to them by renewing their vows at Disneyland. The lavish ceremony was also in celebration of their fifth wedding anniversary.
So we can imagine the sultry singer was giving out a few wedding pointers to all of the fellow happy couples last night!
What do you think of Mariah's wedding dress? Let us know below, as the best comment from across the website each week wins £50!
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