Balotelli, who was born in Palermo to Ghanaian parents and has played 33 times for Italy, has long been a target for racist abuse.
He took to Instagram to target Nigerian-born Toni Iwobi, who was elected in the northern industrial city of Brescia – a major immigration hub.
"Maybe I'm blind or maybe they haven't told him that he's black yet. Disgrace!" Balotelli wrote on Tuesday, in a post that is no longer visible.
A screenshot of Balotelli's post, which was part of an Instagram Story that automatically disappears after 24 hours.
Iwobi has long argued along with League leader Matteo Salvini that increased racism in Italy should be blamed on illegal immigration.
Balotelli posted a photo showing Iwobi and Salvini both wearing 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" and making Italian cities less safe.
Born in Gusau in northern Nigeria but living in Italy since the 1970s, Iwobi has been a supporter of the League for more than two decades.
"I'm not interested in what Balotelli thinks," Iwobi said in response. "He's a great footballer, I hope he sticks to doing what he's good at."
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Tony Iwobi with the League's leader, Matteo Salvini, in 2016. Photo: Tony Iwobi/Facebook