| Jurisdiction: | Diocese |
| Aveiro | |
| Latin: | Dioecesis Aveirensis |
| Local: | Diocese de Aveiro |
| Country: |  Portugal |
| Metropolitan: | Archdiocese of Braga |
| Province: | Braga |
| Rite: | Latin Rite |
| Denomination: | Roman Catholic |
| Established: | 24 August 1938 |
| Cathedral: | Cathedral of St Dominic in Aveiro |
| Area Km2: | 1,537 |
| Population: | 314,800 |
| Population As Of: | 2012 |
| Catholics: | 274,400 |
| Catholics Percent: | 87.2 |
| Bishop: | António Manuel Moiteiro Ramos |
| Metro Archbishop: | Jorge IV |
| Map: | Dioceses de Portugal.PNG |
| Website: | Website of the Diocese |
The Diocese of Aveiro (Latin: Dioecesis Aveirensis) is a Latin Church diocese of the Catholic Church in Portugal. It has existed since 1938 when the historical dioceses of Coimbra, Porto, and Viseu were combined. It is a suffragan of the archdiocese of Braga.[1] In 2012, it had 274,400 baptized over 314,800 inhabitants.
Its see at Aveiro is also the capital of the district of Aveiro. The bishop is António Manuel Moiteiro Ramos, appointed in 2014.[2]
The territory covers 1,537 km² and is divided into 101 parishes, grouped into 10 archipresbiterati, corresponding to the 10 municipalities of the district.