The church has an aisleless nave that continues directly into the chancel, both of the 12thc. and built of red sandstone, a greenish sandstone 15thc. tower and a timber S porch. The chancel is built over a crypt, which once contained the shrine of St Kenelm; the arch in the S chancel wall giving access to it is now blocked. There is Romanesque sculpture in the S nave doorway and on a corbel and two carved panels set in the S wall of the nave.

According to the VCH, Romsley may perhaps be identified with the land in the manor of Halesowen held at Domesday from Earl Roger by Roger the Huntsman; St Kenelm's chapel is not mentioned in the Domesday Survey, but it could have been served by priests of Halesowen.

The ribbed draperies of the tympanum may be inspired by the Herefordshire School, as seen especially at Fownhope. According to Stratford in Pevsner 1968 (254, fn.), Romsley has the only complete beakhead in Worcestershire. The plan of the foundations of St Kenelm's chapel suggests that it was built on a pre-Conquest base.