| Jurisdiction: | Diocese |
| Purnea | |
| Latin: | Dioecesis Purneaensis |
| Country: | India |
| Rite: | Latin Rite |
| Cathedral: | St. Peter’s Cathedral in Purnia |
| Area Km2: | 15,733 |
| Population: | 8,349,215 |
| Population As Of: | 2004 |
| Catholics: | 24,391 |
| Catholics Percent: | 0.3 |
| Metro Archbishop: | Sebastian Kallupura |
| Emeritus Bishops: | Angelus Kujur |
The Roman Catholic Diocese of Purnea (Latin: Purneaen(sis)) is a diocese located in the city of Purnea in the ecclesiastical province of Patna in India.