There has been a parish church at Belstone since at least 1260AD, the date when the first recorded priest, William de Speccot, was appointed. However, at the time, Belstone Church was 'void by official sentence' and it seems probable that a priest was here well before that date. Indeed, the incised granite cross, which stands on the south wall of the Church near the Lady Chapel, has been dated from somewhere between the 7th and the 9th centuries. This indicates that there has been active Christian worship in the area since before the Norman Conquest, and the Manor of Belstone is recorded in the Domesday Book, confirming the existence of an established farming community from the Anglo-Saxon era. Tin streaming on the moor and granite quarrying and cutting seem to have made Belstone wealthy enough to afford to build a church, even in such a remote place.
There is some evidence in the building of its Norman origins, but the present small and solid granite building, built to withstand the Dartmoor winters, dates from the 14th or 15th century. The earliest surviving written record of it is in an 'Inventory of Church Goods' compiled in 1547. The first reference to the Church being dedicated to St Mary the Virgin is later still, in 1738. A contemporary Visitation Report complements the parish on the good state of the Church fabric, but this appears to mark the beginning of a long period of neglect and decline. By the early 19th century a series of reports testified that the whole fabric was in a very sorry state. A partial restoration was undertaken in 1855, including the rebuilding of the singing gallery, a traditional feature of many small churches.
There is also a record of an unusual and distinctive feature of church life in Belstone: men and women were separated during services at this time, with the men sitting on the south side of the Church and women on the north. By the 1870s the church had again become very neglected and decayed, and there was a further major restoration in 1881 which swept away all the old pews, carved rood screen and rotting floor. Much of the present day simple granite church building dates from this restoration.
The ancient font is a relic from the earliest church building, in which parishioners have been baptized perhaps since the time of William de Speccot's day. The organ stood originally in the private chapel of the Tudor manor house, Knole House in Sevenoaks, Kent. The open rood screen was erected as the parish memorial to those killed in the First World War. A granite stone with an incised cross stands in the church; it has stood in various places, being first discovered in a mid 19th century demolition of the Church meeting room and alms houses. It was then part of the Rectory wall, but when this was demolished in the 1930s, the cross was returned to the church and leant against the outside of the north wall. It was placed in its current position in 2005.
The centre piece of the high altar is a copy of the Madonna and Child by Marie Basaili, the original of which is in the National Gallery. There are several fine stained glass windows, most installed as part of the 1880 restoration, but there are modern examples as well. Set in the floor of the south aisle are three 17th century gravestones bearing the names of old Belstone families. There are also some interesting gravestones in the church and churchyard, several of which are listed Grade II.
The arms of King George III are over the vestry door. When King, he ordered that the Royal Arms should be placed in all churches as a reminder that the monarch and not the Pope was the final authority in England.
The peal of 5 bells dates back to 1751 and bear the following inscriptions: 1) God bless the Church; 2) Prosperity to the Parish; 3) God save the King; 4) Thomas Reddaway and Simon Coombe, Churchwardens; 5) I call the quick to church and the dead to grave. In 1995 the bells needed re-hanging and at the same time a sixth bell was added with the inscription: 6) God bless the Parish.