The church is composed of 11th, 12th, 13th, 14th 15th, and 17th century parts having a west tower, a nave with north and south aisles and a rectangular chancel. The west tower is unique in that it is the only round tower of Lincolnshire, most likely pre Norman. Sadly, however, it is hidden behind four sides of a hexagon with clasping buttresses. The church was restored in 1863 by Ewan Christian when the aisle windows were renewed and parts of the chancel and south aisle were rebuilt. Inside, the north arcade, north door and arches between the nave and chancel are Norman and the south arcade is Elizabethan. There is a translation of the charter of Edward the Confessor on a pillar to the right of the entrance of the north door and behind the altar are five carvings depicting Jesus to the centre and four of his apostles; Matthew, Mark, Luke and John, each one can be identified respectively by their additions of a man, lion, ox and eagle. Next to the Lady Chapel there is a memorial area dedicated to two squadrons, 576 and 49 who were based at RAF Fiskerton during the Second World War. In the Lady Chapel there is a brass inlay to the floor of a priest in a cope on which is an oak-leaf motif. This is believed to be 15th century and of Thomas Dalyson, formerly rector of the parish and likely to have been related to the Dalyson family of Greetwell. The font dates from around 1250 as do the arches between the nave and the south aisle.