| St Mark's Cathedral | |
| Location: | Port Pirie, South Australia |
| Country: | Australia |
| Denomination: | Catholic Church |
| Consecrated Date: | 1887 |
| Status: | Cathedral |
| Diocese: | Port Pirie |
St Mark's Cathedral[1] is the main place of Roman Catholic worship[2] in the city of Port Pirie,[3] Australia[4] and is the seat of the bishop of the Diocese of Port Pirie (Dioecesis Portus Piriensis).
The church was inaugurated on 9 July 1882, with the design of architect C. Polain, of Napperby, and was elevated to the dignity of a cathedral in 1887. The church was destroyed by fire on 21 October 1947. The newly restored cathedral was reopened in 1953.