John "Jack" Shearer OBE (30 December 1926 – 12 January 2001) was a Church of Ireland clergyman and the Dean of Belfast cathedral.
After two years in Magheralin Parish, County Down he served for seven years in St Patrick's Parish, Ballymacarrett, before becoming rector of Magheradoll, Ballynahinch.
As dean he worked with his Roman Catholic opposite number to organise combined community services and other bridge building activities.
He continued the tradition of the "Black Santa", holding "sitouts" during the Christmas period which raised millions of pounds for charity and in 1993 was awarded the OBE for services to the community.
During his time as dean he oversaw the major reorganisation of the Cathedral precincts, the provision of facilities at the West Front for physically challenged persons and dedicated the "Patience", "Faith" and "Charity" stained glass windows.