The church has a W tower (13thc), a large, high nave (Anglo-Saxon), a N aisle (c.1200) and a long, square-ended chancel (Anglo-Saxon and later). The W and N doorways are 12thc. (early and late respectively), but plain.

The church at Lyminster (Lolinminster) is mentioned in the Domesday Book. It was a 10thc. Benedictine nunnery (Lyminster meaning 'convent of St Leo'), dependent on Almenesches in Normandy, but was suppressed by Henry VI, and its possessions given to Eton College. As a nunnery, the nave was used as the parish church and the long chancel as the priory church.

The church was restored in 1864 and again in 1884. The E bay of the N aisle, where the font is located, has been used as a baptistery since 1892, but was originally a chapel.

Johnson and Nairn dated the N arcade to c.1160-70, but the presence of stiff-leaf foliage in this relatively unsophisticated context is more indicative of an early 13thc. date. The font is of a type, which was common throughout the county in the late 12thc. and early 13thc., and can also be dated c.1200. Peat and Halsted 1912, p.106, referred to a coffin-slab in the churchyard with a 'coped shape and fluted ornamentation disposed herring-bone fashion', which they dated c.1170. It was not noted by CRSBI fieldworkers.