Katie, 19, has had the words 'Mama lives here' inked in italic lettering on the left-hand side of her lower chest.
The body art is believed to be about Katie's mum Diana and she unveiled it to fans for the first time on Instagram today (17 September).
Katie has lifted up her T-shirt to reveal the tat in a picture and, alongside it, she has confirmed it is her 15th scribing.
The singer said: "Ahhhh I LOVE my new tattoo so excited!!! #mamaliveshere #no15."
Last week, Katie admitted on This Morning that a cyber troll threatened to shoot her while she was on The X Factor.
At the time, Diana spoke out about what her daughter was going through, saying: "We don't like all these bullying tactics.
"I want the British public to get behind her and give her a chance."
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