| Type: | Bishop |
| Honorific-Prefix: | Most Reverend |
| Giovanni Antonio Astorch | |
| Bishop of Lettere-Gragnano | |
| Church: | Catholic Church |
| Diocese: | Diocese of Lettere-Gragnano |
| Term: | 1565–1567 |
| Predecessor: | Sebastiano Leccavella |
| Successor: | Bartolomeo Ferro |
| Death Date: | 1567 |
Giovanni Antonio Astorch or Giovanni Antonio Astorco (died 1567) was a Roman Catholic prelate who served as Bishop of Lettere-Gragnano (1565–1567).
On 7 November 1565, Giovanni Antonio Astorch was appointed during the papacy of Pope Pius IV as Bishop of Lettere-Gragnano.He served as Bishop of Lettere-Gragnano until his death in 1567. While bishop, he was the principal co-consecrator of Felice Peretti Montalto, Bishop of Sant'Agata de' Goti (1567).