A Bord Pleanála has given the go-ahead for the new National Maternity Hospital in the grounds of St Vincent's Hospital in south Dublin.
The development, estimated to cost €300 million, will involve a move from the 1930s building at Holles Street in the city centre.
The permission approves the building of a 244-bed hospital at the new site.
When it became known that the new hospital would be owned by the Sisters of Charity, there were protests over fears the facility would be run under a Catholic ethos.
But the order announced last May that it would end its involvement in the St Vincent's Healthcare Group, relinquishing control over St Vincent's public and private hospitals as well as St Michael's Hospital in Dún Laoghaire.
In a joint statement the Chairman and Master of the National Maternity Hospital, Mr Nicholas Kearns and Dr Rhona Mahony, said: "We are delighted at this news which comes after a huge amount of hard work by very many people to bring the project this far.
"It is a very important milestone and we look forward to ongoing cooperation with St Vincent’s Hospital Group to ensure this vital project proceeds to completion as soon as possible."
Minister for Health Simon Harris said that the granting of the planning permission is a "major step forward for women and children’s healthcare in Ireland."