When Ordnance Survey officers visited in 1839, they observed that the entire interior surface of the walls still retained portions of a strong plaster of lime and sand, and remarked that the place would appear not to be one hundred years deserted. That observation was precise: service had ceased before 1747, after a 1731 episcopal visit by Edward Tennison, Church of Ireland Bishop of Ossory, found the roof and chancel slating so decayed that both wanted re-slating. The new slating was never carried out.

The church's origins reach back to the late twelfth century. According to the historian William Carrigan, writing in 1905, the church and parish of Donoughmore, described in early documents as lying "in Odoch," belonged to the Abbey of St. Thomas in Dublin almost from that abbey's foundation in 1177, with several references to the connection surviving from around 1200 to 1240. The building itself is a nave-and-chancel structure of random rubble construction, roughly seventeen metres long and just over six metres wide, aligned east to west as was standard medieval practice. The southern doorway, formed from local red stone with punch-dressed tooling, retains considerable detail, as does the round-headed chancel arch, the archway dividing nave from chancel, with its cut-stone voussoirs, the wedge-shaped blocks that lock an arch together. Inside the south wall sit a small stoup, a basin once used for holy water, and an aumbry, a recessed wall cupboard used for storing sacred vessels. The east gable preserves a two-light window, and a piscina niche, a small drain used for disposing of water from ritual washing, survives at the east end of the south wall. The west gable, which once carried a double bellcote, no longer stands; a 1942 survey found it being supported by wooden stays at that point.

The graveyard around the church continued to serve the community long after the building fell out of use, with burials in the nave recorded as late as 1933. The chancel contains a late sixteenth-century chest-tomb and a fragment of a medieval graveslab, while two late seventeenth-century graveslabs survive in the south-west angle of the surrounding graveyard.