| St John the Baptist Cathedral, Sligo | |
| Fullname: | The Cathedral Church of St Mary the Virgin and St John the Baptist, Sligo |
| Native Name: | Irish: Ardeaglais na Maighdine Muire agus Naomh Eoin Baiste, Sligeach |
| Location: | Sligo |
| Country: | Ireland |
| Denomination: | Church of Ireland |
| Website: | https://www.dkea.ie/parishes/elphin/#sligo |
| Consecrated Date: | 18th century (25 October 1961 as a cathedral) |
| Groundbreaking: | c. 1730 |
| Diocese: | Diocese of Kilmore, Elphin and Ardagh |
| Province: | Province of Armagh |
| Bishop: | The Right Reverend Ferran Glenfield |
| Dean: | The Very Reverend Arfon Williams |
| Archdeacon: | The Venerable Ian Linton |
St John the Baptist Cathedral, Sligo or more properly the Cathedral of St Mary the Virgin and St John the Baptist, Sligo but also known as Sligo Cathedral is one of two cathedral churches in the diocese of Kilmore, Elphin and Ardagh (the other is St Fethlimidh's Cathedral, Kilmore) in the Church of Ireland. It is situated in the town of Sligo, Ireland in the ecclesiastical province of Armagh.
The church was built as St John's Church in the mid-18th century to the design of architect Richard Cassels, who adopted a basilica pattern from Roman architecture.