Don Girolamo Boncompagni (23 March 1622 â 24 January 1684) was a Roman Catholic cardinal.
He was born in Isola del Liri, the son of Don Gregorio I Boncompagni, 2nd Duke of Sora, Aquino, Arce and Arpino, 3rd Marquess of Vignola, and his wife, Eleonora Zapata, called Zappi and the great-grandson of Pope Gregory XIII. There were several other Cardinals in his family; he was the Grand-nephew of Cardinal Filippo Boncompagni (1572), nephew of Cardinal Francesco Boncompagni (1621) and uncle of another Cardinal Girolamo Boncompagni, archbishop of Bologna (1695).
On 4 February 1652, he was consecrated bishop by Niccolò Albergati-Ludovisi, Cardinal-Priest of Santa Maria degli Angeli e dei Martiri, with Ranuccio Scotti Douglas, Bishop Emeritus of Borgo San Donnino, and Carlo Carafa della Spina, Bishop of Aversa, serving as co-consecrators.
He died in Bologna.
While bishop, he was the principal consecrator of:
and the principal co-consecrator of: