| Jurisdiction: | Diocese |
| Celaya | |
| Latin: | Dioecesis Celayensis |
| Local: | Diócesis de Celaya |
| Country: |  Mexico |
| Metropolitan: | Celaya |
| Province: | Province of León |
| Area Sqmi: | 3,386 |
| Population: | 1,544,000 |
| Population As Of: | 2007 |
| Catholics: | 1,403,000 |
| Catholics Percent: | 90.8 |
| Parishes: | 65 |
| Denomination: | Roman Catholic |
| Rite: | Roman Rite |
| Established: | 13 October 1973 (years ago) |
| Cathedral: | Cathedral of the Most Pure Conception |
| Bishop: | Víctor Alejandro Aguilar Ledesma |
| Metro Archbishop: | Alfonso Cortés Contreras |
| Emeritus Bishops: | Benjamín Castillo Plascencia |
| Map: | Roman Catholic Diocese of Celaya in Mexico.jpg |
| Website: | https://www.diocesisdecelaya.org |
The Roman Catholic Diocese of Celaya (Latin: Dioecesis Celayensis) (erected 13 October 1973) is a suffragan diocese of the Archdiocese of León. It was a suffragan of the Archdiocese of San Luis Potosí until 25 November 2006.