The Dreamgirls actress flaunted her perfect curves in a super-short little white dress designed by Balmain, which featured a plunging neckline and a peplum waist.
The songstress - who has lost an incredible 80lbs since 2010 - paraded her pins in a pair of sheer tights, ramping up the va-va-voom with sexy black pointed courts.
Her deep V-neckline revealed a glimpse of her balconette bra and she accessorised with silver rings, plus a mega-watt smile.
She even gave her fans a sneak peek of her outfit on Instagram, captioning her snap: "Bet honors! Ready to serve! #bethonors."
We also noticed that Jennifer switched up her hair for the evening, ditching her usual slicked-back quiff for a choppy fringe.
The starlet upped the glam on the beauty front too with feline eyes, a pillar-box red pout and a vibrant mani to match.
Jennifer later performed at the event in another white ensemble, this time rocking high-waisted trousers and a sleeveless embellished top.
Meanwhile, Mariah Carey also took to the stage at the ceremony, taking the opportunity to debut her new single, 'You're Mine' (while climbing atop a piano, as you do!)
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