Upton is a spring-line village at the foot of the Berkshire Downs in the Vale of White Horse districty of the county. The church has an aisleless nave and chancel of c.1100 with a timber bell-turret. There are three original windows in the nave and one in the chancel, all uncarved. Romanesque sculpture appears on the S doorway (plain 12thc. N doorway) and chancel arch and a plain font.

A manor was recorded at Upton in the Confessor's reign, held by Beorhtric and assessed at 10 hides. In 1086 it was held by Turstin and assessed at 5 hides. Soon after it passed to Wynebald de Ballon, who gave a moiety of it to Bermondsey Abbey in 1092. This was held by the abbey until the Dissolution.

The church was a chapelry of Blewbury throughout the Middle Ages, until the parish of Upton and Aston Upthorpe was formed in 1862.

The chip-carved chancel arch with its depressed head may date from the end of 11thc. Unusually Pevsner failed to record the doorways. The S doorway lacks capitals, imposts and label and is clearly not in its original state. The voussoirs are of two different lengths, suggesting that they were once in two orders of a grander doorway. If this is so, the four voussoirs containing half-chevrons may have been springers.