The former president has hit out at his successor, but praised the club's appointment of Gerardo Martino as Tito Vilanova's replacement as it will aid Lionel Messi
Laporta, who was in charge at Camp Nou between 2003 and 2010, has regularly criticised Rosell in the past and his latest scathing criticism has seen him label his successor as being too covert with his actions.
"Rosell represents 'neo-Nunez-ism' [referring to ex-club president Josep Lluis Nunez]," he told gathered media at the 50th anniversary presentation of magazine Libero.
"He doesn't act openly. He behaves neurotically and immaturely."
However, Rosell believes that the Catalans' decision to hire Gerardo Martino to replace Tito Vilanova was a great one, especially if it brings to best out of Ballon d'Or holder Lionel Messi.
"The Barcelona dressing room is a complex one and requires time to adapt. I think that signing Tata was a good decision," he added.
"His comments saying that he will have to adapt to the Barcelona system I think is an intelligent attitude to take and I'm sure that he'll do well.
"If signing Martino makes Messi happy, it seems a good idea to me. It's one of the points in favour of this decision."
Martino is set to be unveiled as the new Barca coach at a press conference on Friday.