| Jurisdiction: | Diocese |
| Nicolet | |
| Latin: | Dioecesis Nicoletana |
| Coat: | File:Diocese_of_Nicolet.jpg |
| Coat Size: | 200px |
| Coat Caption: | Logo of the Diocese |
| Country: | Canada |
| Province: | Quebec |
| Catholics: | 189,900 |
| Catholics Percent: | 98.0 |
| Denomination: | Roman Catholic |
| Rite: | Roman Rite |
| Established: | 10 July 1885 |
| Cathedral: | St. John the Baptist Cathedral, Nicolet |
| Bishop: | Daniel Jodoin |
| Emeritus Bishops: | André Gazaille |
| Website: | http://www.diocesenicolet.qc.ca/ |
The Roman Catholic Diocese of Nicolet (la|Dioecesis Nicoletana) (erected 10 July 1885) is a suffragan of the Archdiocese of Sherbrooke, Quebec, Canada.
The seat of the bishop (or "ordinary") is the Cathedral of St. Jean-Baptiste, a spectacular building opened in 1963, which seats 1,200 worshippers and features extensive stained glass as well as other artwork by a number of local artists. The present building is the fifth cathedral, successor to four previous buildings that fell victim to various physical disasters: two collapses, a fire, and damage from the Nicolet landslide of 1955. A frieze of stained glass in the apse shows characters from the Bible and from the history of the Christian church, including a portrait of Bishop Martin, who was responsible for construction of the new building.