St Brendan's is a parish in Coolock, Dublin in Ireland that is served by the Church of St Brendan. The parish is in the Fingal South East deanery of the Roman Catholic Archdiocese of Dublin. The parish is based on the civil parish of Coolock. During penal times, it was one of the few functioning Catholic parishes in Dublin.

Coolock is a large suburban area, centred on a village, on Dublin city's Northside in Ireland. Coolock is crossed by the Santry River, a prominent feature in the middle of the district, with a linear park and ponds. The Coolock suburban area encompasses parts of three Dublin postal districts: Dublin 5, Dublin 13 and Dublin 17.