Katona was signing copies of her new book Still Standing: The Autobiography at WHSmith in her hometown of Warrington yesterday (November 30) when she debuted the new cut.
The former I'm a Celebrity Queen of the Jungle told a friend on Twitter that she was so nervous when the clippers came out that she "had to hold my mum's hand lol :-)".
Katona recently spoke to Digital Spy about her new healthier look and lifestyle.
She said: "My exercise regime used to be a kebab and a line of coke.
"I've been doing drugs since I was 14, I've been on medication and I got my first natural high from going to boot camp. The endorphins were amazing."
Katona's autobiography is out in shops now.
Watch Digital Spy's chat with Katona below: