The Italy striker was caught smoking a cigarette in the bathroom on a train carrying his AC Milan squad to face Fiorentina on Sunday and club vice-president Adriano Galliani says Balotelli will be fined.
Coaches have been trying to get Balotelli to quit smoking for years and the practice is banned on Italian trains.
Balotelli should have plenty of time to mull over his latest act of misbehaviour as he picked up a yellow card in the 2-2 draw with Fiorentina which rules him out of next weekend's showdown with Napoli, the team Milan is trying to catch for second place and a direct Champions League berth.
Besides his numerous run-ins with coaches, Balotelli has a history of off-pitch misbehaviour.
He made light of his troubles in 2011 when he was with Manchester City by unveiling a T-shirt with the slogan "Why Always Me?" during a 6-1 rout of Manchester United in a Premier League derby. That came after news emerged that a fire had broken out at his house when fireworks were let off in his bathroom.
Balotelli escaped punishment earlier in 2011 after throwing a dart at a City youth-team player. No one was hurt in the incident.