Nave tall, the walls plastered, and an open timber barrel vault with five moulded runners, rising from wall plates carved with alternating masks and shields, one, towards the W on the N side bearing the date 1471. Chancel arch of 2 wave orders, dying into square abutments, probably late C15. One step up into the chancel, which is also plastered, and which has a depressed timber panelled vault with centre and end trusses, C19. Two steps to the sanctuary which has encaustic tiles. Stone corbels either side of the E window. In the E nave, stone brackets for a wide rood loft, which has a square opening, probably originally a door, through the chancel wall, perhaps for viewing the altar. The loft stair was noted on the N side of the chancel in 1848. Tall tower arch, raised when the upper part was rebuilt in the later C15, and a 4-centred arch to the tower stair, and a medieval mensa re-used as a threshold.
Fittings: Font, of gritstone, octagonal and C15 - C16, with chip-carved roundels alternating with elementary but symbolic carved triple trees, a type paralleled at Llanharry and Llantrisant. Stem broached to the medieval base which has ball motifs on the base chamfer. Pulpit, part octagon, mid-later C19, of alabaster. Gothic arches meeting at serpentine colonettes at the angles, and a limestone figure of St James. The bookrest is supported by an angel, the whole replacing a former timber pulpit in c.1919, and set on a broached limestone base. The former pulpit appears to have been reached from the chancel by a door opening. Sanctuary rail of brass on brass sheathed scrolled stanchions. Linenfold panelling on E wall with a gilded and carved wood reredos diplaying the Crucifixion, a memorial gift to Rees Rees, C20. Pews C19 of pine.
Monuments: (a) Limestone slab with half-round top to Rees Thomas, d.1680, and wife d.1689; (b) Steeply pedimented aedicule with simple side columns flanking a limestone slab to Edward Thomas of Cornely, d.1693, and wife Ann; and on E wall, (c) limestone slab with separate semicircular top to Joseph Lewis of Pill, d.1698, and wife Anne, d.1715. In Nave: (d) White marble oval on black, by Rogers, to Margaret Collier, d.1847; (e) White marble oval tablet on black oval, to James Simpson, d.1832, and family; and (f) similar, to Margaret Jones, d.1857. A Great War memorial is set on the chancel N wall.
Bell: One dated 1677.
Glass: E window, Light of the World and Crucifixion by Charles Powell of London, 1921; Nave NW window, Good Samaritan by Karl Parsons, 1931-2 given by the RAOB, good; Nave NE, Moses, c.1922; Nave SE, David and Jonathan, 1927 by William Glasby of London. South Chancel, SS James and John by ALW, 1950.