There are a small number of heritage railways in the Republic of Ireland, reflecting Ireland's long history of rail transport. Some former operations have closed, and aspirant operations may have museums and even rolling stock, but no operating track. There are also working groups, which may run heritage rolling stock on main lines.

• Castlerea Railway Museum, County Roscommon
• Cavan and Leitrim Railway, County Leitrim
• The Donegal Railway Heritage Centre in County Donegal, commemorating the operations of the County Donegal Railways Joint Committee which once had two narrow gauge railway systems

Preservation groups in the Republic of Ireland include:

• The Irish Steam Preservation Society, based in Stradbally, County Laois, which operates the Stradbally Woodland Railway with vintage steam and diesel locomotives.
• The Irish Traction Group, based in Carrick-on-Suir, County Tipperary, which has a diesel locomotive collection at the site by the Limerick–Waterford railway route. ITG also run regular railtours around the country, sometimes with older (but still in regular use) Iarnród Éireann locomotives and rolling stock.
• The Railway Preservation Society of Ireland, an all-island body, with bases in County Antrim and Dublin, and a museum in the former; holds a full operating licence and operates heritage-themed excursions on the main lines in both jurisdictions.