Giambattista Eustachio (1622âÂÂ1687) was a Roman Catholic prelate who served as Bishop of Lucera (1663âÂÂ1687).
Giambattista Eustachio was born in Troia, Italy in 1622. On 12 February 1663, he was appointed Bishop of Lucera by Pope Alexander VII. On 18 February 1663, he was consecrated bishop by Benedetto Odescalchi, Cardinal-Priest of Sant'Onofrio. He served as Bishop of Lucera until his death in September 1687.
While bishop, he was the principal co-consecrator of Ulysses Rossi, Auxiliary Bishop of Sabina and Titular Archbishop of Salamis (1681).