Interior
The porch has an arched-brace roof on corbels. It has stone side benches, a large crudely worked stoup, and a shallow niche above the doorway. The doorway, with plain 2-centred arch, has double doors inserted in 1988, but the earlier door, dated 1717 and incorporating vertical studded ribs, has been retained inside the porch. Above the inner face of the doorway, in the nave, is a small carved head, probably re-set.
The main interior has been stripped of plaster. The nave has a 2-bay N arcade with octagonal pier and 4-centred arches. The arched-brace nave roof is 12 narrow bays. The chancel arch, narrowed but with the earlier arch still visible in the wall, is steeply pointed. To its L is a squint, and to its upper R is a former rood-loft doorway. In the W bay of the nave is a blocked segmental-headed tower window. The SE nave window appears to have been associated with a tomb recess as the embrasure continues to the ground. The relieving arch above a former window can be seen above the present window, however. The window has an ashlar embrasure with finely-moulded rere-arch and its soffit is decorated with arms of Butler and Beaufort families, and a shield bearing the 5 wounds.
The chancel has an arched-brace roof of 6 narrow bays, similar to the nave. It has a 2-bay N arcade, also similar to the nave. A recess is in a former S doorway. The E wall has a simple wood-panelled reredos. To its L is a tiny corbelled rectangular piscina, and an aumbry with pointed head. In the N aisle and the Lady chapel are embossed wagon roofs but not ceiled. A narrow pointed arch is between aisle and chapel. The 2-centred tower arch is continuous with a rendered tunnel vault.
The slender octagonal font is Perpendicular in style, of 1856, with quatrefoils around the bowl. The polygonal wooden pulpit, dated 1911, stands on a narrow bracketed base. Each facet has ogee-headed panels with marginal vine-trail decoration in low relief. Plain pews have moulded square ends. The choir stalls have richer moulded ends and the front rank has an open frieze of quatrefoils in lozenges. The early Georgian communion rail has turned balusters.
There are numerous wall monuments. The recess in the chancel S wall has an oval tablet to Rev Thomas Morgan (d 1817). Memorials to the Rees family of Cilymaenllwyd are in the nave S wall. The best is to John Rees (d 1802), an alabster sarcophagus with inscription, surmounted by a draped urn, on a triangular slate background. Others include slate tablets to John Rees (d 1843), Hector Rees (d 1760) and a brass memorial to Mansel Rees (d 1889). An oval marble tablet also in the S wall commemorates Robert Jones (d 1789).
In the nave W wall are 3 superimposed memorials. At the top, a corbelled marble panel to Anne Miller (d 1861), by Philip Rogers of Swansea, the next a marble panel on slate background, to Udea Onslow (d 1868), also by Rogers, and a less-well preserved slate memorial to Bennet Richards (d ?1748). In the N chapel, starting at the NE end, is a plain large marble panel to Edward Rees (d 1864) and family, on a slate background, by D Joslin of Peckham Rye, then a polished granite memorial to Lt Col David Williams (d 1852). Further L is a plain panel on a slate background, to Capt Benjamin Williams (d 1865), also by Joslin. Below it is a wooden benefaction board.
The E window depicts the Crucifixion, by Horace Wilkinson and dated 1926. The N chapel E window depicts the Nativity, by Celtic Studios of Swansea, but undated. In the nave S wall is Christ and Mary Magdalene, mid C20.