St Issel's Church is situated within a large, irregularly shaped churchyard, which has been extended to the south-east but was originally rectilinear. A stream bisects the churchyard from north to south, some 20m west of the church building. The three pairs of churchyard gates, North Churchyard Gates (NPRN 418895), Rear Churchyard Gates (NPRN 418906) and South Churchyard Gates (NPRN 418907) are Grade II listed. The gates were reportedly fabricated at the Kilgetty ironworks. A restored medieval churchyard cross (NPRN 304234) stands to the immediate north of the church. In the 12th century the church was a possession of Seez Abbey, Normandy (possibly as an appropriation of Monkton Priory), but the abbey granted it to the Canons of St Davids before 1224. The original dedication to St Usyllt, reputed father of St Teilo, may make the church one of a group of pre-Conquest 'Teilo' churches in the region.

The church consists of nave, chancel, north aisle, south aisle, south porch, north vestry and west tower. The square, oolic limestone font is thought to be twelfth-thirteenth century in date. It has a slightly different design on each face, with raised scroll faces and apparently randomly placed stars and crescents. Its limestone stem is thought to be two reused twelfth or thirteenth century column caps. The chancel arch is also medieval, as is the north arcade. The church was restored extensively in 1862, to the designs of J.R. Kempson, Hereford. Only the tower was retained, with the rest of the building being rebuilt. The original layout was retained,but the floors were raised. A window at the south end of the chancel is dedicated to the Rev. John Jones, Vicar (1888-1912), and depicts the restored church, held as a model in the hands of St. Issell. The church reopened in 1864. The vestry was added in 1910 and the pews were renewed throughout. After the First World War a new pulpit, by Caroe, was constructed as a memorial, incorporating the roll of honour. It is carved in Perpendicular style and depicts St George and the dragon. The porch doors and a flight of curved-plan steps were added in 1978 in memory of the third Lord Merthyr.

Sources include:
Cadw, Listed Buildings Database
Cambria Archaeology, 2003, Early Medieval Ecclesiastical Sites Project, Pembrokeshire gazetteer

N Vousden, RCAHMW, 15 May 2013