The church consists of chancel, nave, S porch, S transept and W tower. The upper part of the tower is 17thc. The lower part is 12thc. There is a plain round-headed 12thc. window above the tower arch, edged by a keeled roll. The chancel was rebuilt in the 13thc. to14thc. and the S transept added at this time. The 12thc. nave survives, this has a plain 12thc. window to the W of the S doorway. The chancel arch and several reset fragments bear 12thc. sculpture.

The Domesday Survey does not mention a church at Knotting, but records that the Bishop of Coutances held land there. VCH records that on the Bishop's death, the land reverted to the King and that it was later granted to the Ferrers family who held it until the 17thc. (VCH, 139).

The church was originally a chapel to Melchbourne Church (Bedfordshire). In 1176 the Bishop of Exeter, resolving a dispute, judged that the chapel should be the property of the Prior and Convent of St Neots and should be free of Melchbourne. In 1190 this was confirmed by Hugh of Lincoln. (VCH, 142)

In the mid-13thc. the Priory lost the advowson and by1275 Hugh Bossard, Lord of Knotting held it. The advowson remained with the Bossard family until the 18thc.