This isolated medieval church is set on a small hillock a few minutes walk away from the Aylesbury to Bicester road. Surrounded by trees, in the middle of fields, it consists only of a nave, chancel, and porch. The village it served has long since disappeared, although Methodist founder John Wesley preached here soon after he was ordained, and the church was restored by Sir G Gilbert Scott in 1868.
The church was built in the twelfth and thirteenth centuries, probably on the site of an earlier church. There is a quaint Norman font, a beautiful chancel arch rebuilt in the fourteenth century, and a fine fifteenth-century queen-post roof over the nave.
Fleet Marston was originally a separate benefice but in August 1931 it combined with Over Winchendon in a union of benefices under an Order in Council. In February 1973, an Order in Council combined the united benefice with Waddesdon to form the current parish.
The church was declared redundant in January 1972, but because of its historical and architectural interest, it was transferred to the Redundant Churches Fund by an Order in Council of August 1973. It is now managed and maintained by the successor organisation, the Churches Conservation Trust.
Under the transfer agreement, the parish can hold up to six services a year in the church. In recent years, a service has been held on the Sunday of the August Bank Holiday weekend.