The 26-year-old brunette took to social media on Sunday, claiming the male hairdresser hacked at her brunette strands and ruined her fringe.
"I don't know what they did," she said in a video, while pulling at her lopsided locks.
"I told him I like little pieces on the side like a curtain fringe and this is what he gives me.
"My fringe is literally shorter at the back than it is at the front. What the f**k?"
Morello, who posted a throwback photo of her hair in better times on Instagram on Sunday, said she wasn't able to stop the hairdresser from hacking in to her fringe.
"I told him as he cut my fringe and freaked out, pulled away and said 'no no I wanted a long curtain fringe' but he had already done it," Morello posted.
"Then he curled it a bit as he dried it so I couldn't see how bad it was till I got home and straightened it."
It is understood the Sydney-based blogger received an offer to have her hair fixed by the salon, but she declined in favour of going elsewhere.
"I've booked in with @CloAndFloHair I know they can't make hair grow back but maybe they can disguise the mess that T & G did for a while," she said on Twitter.
Morello's scathing post was met with sympathy on social media, with hundreds of fans posting about similar experiences with the hairdressing chain.
"I went to T & G in Melbourne a while back asking for a fringe. Literally half my hair was cut into one," one user posted.
"I looked like I had a mullet! They offered to fix it, but I never went back."
Other fans slammed the salon, questioning how "professionals" could allow a haircut like Morello's happen.
"Can't believe what he did to your hair," one person said.
One Instagram user, who claimed to be employed by Toni & Guy, said she was "gutted" to hear about Morello's experience.
"I promise you not all Toni & Guys are the same, we have some really amazing salons and really amazing individuals," the employee wrote.
"It's just super sad that not all the salons are doing what they should be. I hope you get sorted soon."
When contacted by news.com.au, a spokesperson for Toni & Guy Australia said they were "very disappointed" to hear of Morello's experience.
"Whilst the incident was not a result of any service provided by Toni & Guy Australia, we empathise with Chloe's distress," the statement read.
"Our Toni & Guy Stylists undergo rigorous training and are required to operate at a high skill level.
"We service over 4000 clients a month, and every day we strive to ensure our clients leave our salons feeling their best.
"Being that hairdressing is very personal, this is sometimes not the case, and we strive to work with our clients to ensure we get it right.
"This incident is most definitely not a representation of Toni & Guy, a brand that prides itself on leading hair trends as well as servicing loyal repeat clients."
