St Cadoc's Church, Llangadog, is medieval in origin. It is situated within a curvilinear churchyard, bounded by Church Street on its west side. The churchyard is thought to possibly be associated with a very large former outer enclosure.

The cruciform church is a Grade II listed building, constructed of limestone rubble with ashlar dressings, and slate roofs with red terracotta ridges, alternately crested. It consists of five-bayed nave, two-bayed chancel, north and south transepts, west tower with three storeys and south porch. The ground plan of the church is thought to have changed little from its original plan.

The tower is 14th century, and is unbuttressed, with a battered plinth and a corbelled, embattled parapet (restored in 1894). One late medieval, two-light flat-headed window with arch-headed lights survives on the north side. The church is thought to have had an eastern apse, whose foundations were met with at the time of the 1889 restoration. The octagonal font is late medieval in date. The church was repaired in 1694, according to a plaque on the tower.

In 1889 the body of the church was extensively restored and partially rebuilt, including new roofs, porch, north walls, south transept, windows and tower parapet. Prior to the 1889 restoration the church is said to have had a 'rude mural painting of the Doom' (now lost). The stone pulpit with Gothic panels dates to 1889, and the pews and organ in Gothic case also date to the late 19th century.

Sources include:
Cadw listing database
Cambria Archaeology, 2000, Carmarthenshire Churches, gazetteer, pp. 48
Richard Suggett, Painted Temples: Wallpaintings and Rood-screens in Welsh Churches, 1200–1800, (RCAHMW 2021).

RCAHMW 2022