St. Maelruain's Church is a church of the Church of Ireland located in Tallaght, South Dublin in Ireland. The parish is in the United Dioceses of Dublin and Glendalough. It occupies the site of the original Tallaght Monastery. The present-day church was built in 1829 on a grant of £300 by the Board of First Fruits. It replaced an earlier one to which the still-existing tower belonged. Lewis reported that that church was "in the pointed style of architecture, with pinnacles at the angles and along the sides".;