| Jurisdiction: | Diocese |
| Versailles | |
| Latin: | Dioecesis Versaliensis |
| Local: | Diocèse de Versailles |
| Country: | France |
| Province: | Paris |
| Metropolitan: | Archdiocese of Paris |
| Area Km2: | 2,270 |
| Population: | 1,441,147 |
| Population As Of: | 2014 |
| Catholics: | 935,000 |
| Catholics Percent: | 64.9 |
| Denomination: | Roman Catholic |
| Established: | 29 November 1801 |
| Cathedral: | Cathedral of St. Louis in Versailles |
| Patron: | St. Louis IX of France |
| Metro Archbishop: | Laurent Ulrich |
| Suffragan: | for one --> |
| Archdeacon: | for one--> |
| Emeritus Bishops: | Éric Aumonier |
| Map: | Diocèse de Versailles.svg |
| Map Alt: | Locator map of Diocese of Versailles |
| Website: | Website of the Diocese |
The Diocese of Versailles (Latin: Dioecesis Versaliensis; French: Diocèse de Versailles) is a Latin diocese of the Catholic Church, in France. The diocese, headed by the Bishop of Versailles, was established in 1801. Until then, its territory had mostly been part of the Archdiocese of Paris and the Diocese of Chartres. It was centred on Versailles.
On its creation, the territory of the diocese of Versailles corresponded to the département of Seine-et-Oise. Following the boundary changes of the départements of Île-de-France, new dioceses were established on 9 October 1966. The diocese of Versailles was therefore modified to correspond to the département of Yvelines, following the creation of the Dioceses of Évry–Corbeil-Essones, Nanterre, Saint-Denis, Créteil, Pontoise.