Born in the Sicilian capital of Palermo to Ghanaian parents and having played 33 times for Italy, Mr Balotelli has been a consistent target for racist abuse.
The international footballer took to Instagram to blast Nigerian-born Toni Iwobi, who was elected as a senator in the northern-Italian city of Brescia.
“Maybe I’m blind or maybe they haven’t told him that he’s black yet. Disgrace!” Mr Balotelli wrote on Tuesday, in an Instagram post that is no longer available.
He also posted a photo depicting Mr Iwobi and leader of the League party, Matteo Salvini, both donning t-shirts emblazoned with the campaign slogan “Stop Invasion”.
The slogan is reference to the more than 690,000 migrants who have landed on Italian shores from North Africa since 2013.
The League blames the arrivals for “social conflict”, increased racism and making Italian cities less safe.
Born in Gusau in northern Nigeria but living in Italy since the 1970s, Mr Iwobi has been a supporter of the League for more than two decades.
“I’m not interested in what Balotelli thinks,” the new senator said in response to the fiery post, adding that he’d prefer to ignore his critic.
“He’s a great footballer, I hope he sticks to doing what he’s good at.”
Mr Salvini was less diplomatic in his response to Mr Balotelli’s comments.
“I didn’t like Balotelli on the field, I like him even less off it,” he said.
Mr Salvini has taken a hardline stance on the migrant crisis and called for mass deportations after Nigerian migrants were arrested in relation to the murder of an 18-year-old woman whose dismembered body was found in two suitcases near Macerata.
Former League activist and right-wing extremist Luca Traini, 28, shot and wounded six African migrants in Macerata days later, claiming he was avenging the woman.
Several League members have made racist comments in the past.
Northern League MEP Mario Borghezio was ordered to pay Italy’s first black minister, Cecile Kyenge, €50,000 in compensation over racial slurs last year.
Mr Borghezio reportedly said, among other things, that “Africans are Africans and belong to an ethnic group very different from ours”.
Born in Congo, the ex-minister was the target of racism from other party members: in November 2013, Northern League senator and former minister Roberto Calderoli compared Ms Kyenge to an orangutan.