The 40-year-old is accused of abusing at least four boys, aged between 13 and 16, at the oratory school in a Milan suburb, La Stampa reported on Tuesday.
He was put under house arrest and ordered to wear a tracking bracelet.
An investigation into allegations of sexual abuse began in 2011, after one of the victims told his parents what had happened to him.
Police were then able to identify the three other teens reportedly abused, although believe that there may be more victims, the newspaper said.
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