Runestones found in the area suggest the site may have held Christian significance as early as the mid-1000s, and a wooden church may have stood here during that century. The place-name Torsvallen hints that an earlier pagan temple dedicated to the god Thor might once have occupied the site, though this remains speculative. Archaeological remains of an apse church from the 1100s, uncovered beneath the present building during restoration work in 1955–1956, confirm a stone church existed here from that period.
The exact date the current church was begun is debated: one scholar has argued for the late 1200s, another for the second half of the 1300s. What survives from this building phase is the chancel and the easternmost part of the nave. The church was later enlarged with a sacristy in 1736, an additional vaulted bay in 1742–1743, and a tower in 1776–1777 designed by the architect Olof Tempelman, to which the bells were moved from an earlier freestanding bell tower.
Inside, wall paintings from the 1400s were uncovered during the 1955–1956 restoration and are attributed to the so-called Tierp school of church painters. Among the images are depictions of St Sigfrid, shown with the vessel containing the heads of his murdered nephews, and St Dionysius carrying his own severed head, patron saint of Paris. A further image on the north wall is thought to represent St Anne, once the patron saint of Valbo parish.
The chancel window, created by artist Harald Lindberg (1901–1976), depicts John the Baptist baptising Jesus, chosen in reference to a medieval side altar once dedicated to St John. Flanking sculptures by Ivar Lindekrantz show the Virgin and Child and two apostles, while a silvered bronze crucifix is the work of Arvid Backlund; all were added during the 1955–1956 restoration, along with a new freestanding altar of red sandstone.
Most of the church's medieval silver was lost in thefts in 1891 and 1907 and has since been replaced, but the font dates from the late 1600s, with a wooden stand from 1688 and a pewter basin from 1690. A persistent local claim that Carin Fock married Hermann Göring in Valbo kyrka is incorrect; it was her first marriage, to Niels Gustav von Kantzow, that took place here. Visitors may also encounter a runestone standing outside the church, said locally to be linked to a folk tale about a farmer who borrowed it and lived to regret doing so.