The 46-year-old singer attended a special event for U.N. Secretary-General Ban Ki-moon hosted by RatPac Entertainment at Hilhaven Lodge on Wednesday night in Los Angeles, sporting a skin-tight leather jacket and matching leather pants. Mariah left her jacket halfway unzipped to reveal her lacy black push-up bra, and finished the sexy look with a towering pair of lace-up heels.
And she was clearly feeling herself on the blue carpet, coyly twirling her hair for the cameras.
This isn't the first time Mariah has worn her lingerie during a night out. In June, she rocked a racy black corset during her first-ever DJ set at the 1 OAK nightclub inside the Mirage Hotel and Casino in Las Vegas.
Mariah talked to ET that same month about her personal weight struggle over the years, when she admitted that she's now on a "bleak" diet to maintain her noticeably slimmed-down figure.
"The funny thing with me is I would always be like, 'Oh! I gained weight,' because I am muscular, so sometimes I don't even notice it," she shared. "Now I have been pretty consistent with this bleak diet that I am on."
... Just don't ever expect to see her at the grocery store.
"Grocery shopping? It's pretty bad lighting in the grocery store!" Mariah laughed. "Have you not noticed it's fluorescent lighting?"
Clearly, everything the GRAMMY-winning does is fabulous. The "Infinity" singer recently gave ET an exclusive tour of the yacht she's vacationing on this summer, which features two bars, six bedrooms, a Jacuzzi, a gym, a library and a private chef. Her fiance, billionaire businessman James Packer, also has his own yacht -- the Arctic P, which the seventh largest privately owned vessel in the world.
"It is important to have his-and-hers everything," she explained to ET.