The present church consists of a nave and chancel, with north aisle. There is a tower of four stages, the lower three of which were constructed in the 15^th century. The upper story and spire date from the 19^th century. There is a small porch on the north side of the nave wall. The Romanesque parts of the building are two, three bay arcades on the north side of both the nave and chancel. There is also a series of corbels heads, re-set into the north wall of the nave, some of which may be of 12^th century origin.

An auxiliary fort, ‘Derventio’, had been established on the banks of the nearby river Derwent late in the 1^st century, with a large urban settlement expanding over the subsequent period of Roman occupation. There was some form of wooden castle at Malton, which had been constructed in the late 11^th/early part of the 12^th century, though it would appear to have been founded on the remains of Roman earthworks. The castle had been granted by Henry I to Eustace Fitzjohn, though he subsequently sided with the Scottish King David at the so-called ‘battle of the Standard’ in 1138, at nearby Northallerton. After defeating the Scots, the King’s forces, led by Archbishop Thurstan of York besieged the castle. The castle was subsequently rebuilt in stone by Eustace de Vescy. A visit by Richard I in 1189 has been recorded. Though details for the period following the Conquest are very sparse, records from the early part of the 13^th century point towards Malton’s importance as a trading centre. The church of St Leonard was constructed as one of two chapels of ease for the Gilbertine Priory of St Mary which was established shortly after c.1150. Both St Leonard and the second chapel of St Michael are situated in, what became known as, ‘New Malton’, as distinct from ’Old Malton’, which is approximately one mile away and which had been severely affected by a fire in 1138. The remains of the Gilbertine priory are in ‘Old Malton’. The tower at St Leonard was added in the 15^th century. The two chapels of ease became separate ecclesiastical parishes in 1855. The church was the subject of an extensive restoration in 1907, by Hodgson Fowler, during which the south walls of the nave and chancel were completely reconstructed. In 1971, St Leonard was gifted to the Catholic Church, becoming the first parish church to be returned to Roman Catholic use since the Reformation.

The fire that was recorded as having taken place in 1138 was, in all probability, part of the collateral damage to the town, during the besieging of the castle. It is known that the Gilbertine Priory was founded shortly after c.1150, though the centre of commercial activity for the town appears to have already been shifting to New Malton by this date. Archaeological evidence has indicated that New Malton was laid out on a grid system, with some perimeter walls, suggesting attempts to retain the town’s importance as a trading centre. This would be consistent with regarding the construction of nave and chancel of St Leonard’s as having taken place in the second half of the 12^th century, once the Gilbertine Priory was fully functional and occupied. The plain and functional carving of the capitals in the nave would indicate a period c.1170, with those of the chancel a little later.