The quirky singer, 28, left little to the imagination in the seriously figure-hugging outfit and she teamed it with a pair of black peep-toe heels and a chunky necklace.
Despite the chilly February temperatures, Katie slipped off her jacket outside the Universal bash, meaning she also gave photographers a flash of her cleavage and huge arm tattoo.
It takes a brave person to wear a dress that tight, but if anyone has got the nerves, then it's going to be Katie!
But although she was clearly loving it, Katie admits her father Maurice wasn't too impressed by her outfit choice.
She told her Instagram followers: "My mama says that dress is every father's worst nightmare haha love you papa #thebrits."
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The Brits 2014 red carpet in pictures:
Copyright: WENN Lia Toby