The 22-year-old slammed Ferne, 24, and claimed that she'd kissed 'untold geezers' while in the Spanish city.
He told OK! Online: "Ferne McCann was the loosest girl in Marbella. She's loose. She goes out, gets hold of untold geezers then comes in the next day and causes trouble."
Tommy then suggested Ferne is to blame for the breakdown of her relationship with Charlie Sims.
He said: "She's outspoken on people and their relationships because she has nothing going on for herself.
"Charlie and her were together for convenience, I think. She always wanted to break out of that shell."
Ferne and Charlie, 23, broke up earlier this year, when he took to Twitter to quit the show and dump her at the same time.
Tommy, who is seeing fellow The Only Way Is Essex star Georgia Kousoulou, came under fire during the last series of the reality show when it was rumoured that he'd cheated on her.
While Ferne is yet to respond to Tommy's comments, we're sure it won't be long…