The Heritage Council says its popular grants programme will be scrapped unless it gets an increase in its level of funding in the Budget.
The Grants Scheme supports hundreds of projects related to Ireland's heritage.
The programme is open to projects run by community groups, non-Governmental organisations and local authorities.
The Council says it has suffered substantial cuts in its funding since 2008.
Its funding has dropped more than 60% over the past four years, from €20m to €7.5m.
The council says it used funding reserves to offer grants in support of conservation, education and research projects in 2012, but adds "there is now no reserve".
It warns that "the loss of the grants would be a real and significant loss to the heritage sector and to society more widely".