The church comprises chancel, aisleless nave and round W tower. All that certainly survives from the 12thc is the W tower and the S doorway. The nave was rebuilt, or perhaps renovated, in the 13thc, as the lancet window in the S wall indicates. The interior of the church was remodelled in the 15thc when a new arch to the tower and to the chancel was inserted. The date of 1849 above the S doorway probably records a refurbishment at that date. Romanesque sculpture is found on the S doorway.

In the hundred of Blofield, Hassingham, with the village of Limpenhoe, paid dues to the king before 1066. It was held by Earl Ralph before the Norman Conquest but at the Domesday survey, was held from King William by Godric.

The doorway is described by Pevsner as Late Norman, perhaps because of the chamfered jambs. These might not be original, in which case the doorway may have been salvaged from an earlier build and reset as we see it, minus its colonnettes and capitals. Syncopated billet of the type described here was also used at Norwich Cathedral, in the apse arcade (1096-1118). It is also found on doorways elsewhere in the county, for example at St Andrew's, Barton Bendish.