The Church of Annunciation in Finglas has announced it will celebrate its final mass on October 7, before it is demolished and replaced with a much smaller church.
The church, which has a capacity of 3,500, is one of the largest Catholic churches in the country, but attendance had dropped significantly in recent years.
The new church will have a capacity of just 350.
The announcement was made on the church's Facebook page today.
The post read:
'**VERY IMPORTANT ANNOUNCEMENT**
'We are now in a position to announce that the LAST MASS in the church of the Annunciation will take place on Sunday 7th October at 11am.
'Mass will be celebrated by Archbishop Diarmuid Martin. All are welcome at the mass and please spread the word to those who may not be on social media.
'Please note all other updates regarding the closure of the church and arrangements while our new church is being developed will be posted as soon as we are aware of same.
Parish priest Fr Eamann Cahill said previously that attendance was a worry.
In a statement last year he said: "“Following recent research, discussion and much analysis, the parish pastoral council, the finance committee and the parish team agreed that it would be best to replace the present church building with a new church.”