St John the Baptist Anglican Church is an active Anglican church located between Alt and Bland Streets, Ashfield, a suburb of Sydney, New South Wales, Australia. Founded in 1840, on land donated by Elizabeth Underwood, the church building is the oldest authenticated surviving building in Ashfield, having been built at the time when subdivision increased the population density sufficiently to turn Ashfield into a town. It was also the first church built along the Parramatta Road which linked the early colonial towns of Sydney and Parramatta. The earliest remaining parts of the building are one of the first Sydney designs by the colonial architect Edmund Blacket, who later became renowned for his ecclesiastical architecture.