The AC Milan striker has been banned for three games for making insulting and intimidating comments towards the referee after Sunday's 2-1 home defeat by Napoli in Serie A.
Mancini, who coached Balotelli at City for almost three seasons, said to Gazzetta dello Sport: "There is only one way to end this and that is for Mario to learn to resist those anger attacks.
"He must break that spiral. If word spread that he no longer reacted to that, then he would not be a target."
Balotelli made headlines during his time in England for bad behaviour on and off the pitch.
Mancini believes the Italy international is an easy target for rival teams.
"All the defenders in the world know that it only takes two kicks to see him (Balotelli) lose his mind and hence, they do that," Mancini said. "In England I had to have words with some of the players that marked him.
"That happened on occasions where they were clearly provoking him.
"But more or less, everyone tries to have him sent off."
The 23-year-old Balotelli joined AC Milan from City in January and has been a regular in Massimiliano Allegri's side.
"I think Allegri is doing a good job, but it is not easy to coach Mario because when he is not blinded by anger, he is able to listen patiently to reprimands and then promises that he will not make the same mistake again," added Mancini.
"He is sincere but as soon as there is another outburst, you are back to square one."