Some researchers date the earliest parts of Torpa kyrka to the first half of the twelfth century, placing it among the older church buildings in central Sweden, from the so-called mission period. Unusually, the church appears to carry its builder's signature: reliefs on the original south portal include a runic inscription said to read "Ödulf made the church", making it one of very few Swedish churches linked to a named craftsman in this way.
The building is a two-aisled hall church with a straight-ended chancel, built of rendered masonry beneath a saddle roof clad in sheet iron. What is now the chancel was originally the nave of the Romanesque church; the present, later nave was added to the west, with sources differing on whether this took place in the fourteenth or fifteenth century. Above the nave a medieval roof structure survives, altered when vaulting was later inserted, while seven medieval roof trusses above the sacristy—the former chancel—are considered a fine example of early medieval carpentry.
The church's wall paintings were added in several campaigns spanning at least six periods, giving the interior a layered, richly decorated character. The oldest fragments are said to date from the later twelfth century, with further work following in the 1480s. In the chancel arch a painting of the Fall of Man, from the fifteenth century, is among the most striking scenes for visitors to look out for.
Among the furnishings, the font is the oldest surviving item, dating from the twelfth century. A triumphal crucifix from the mid-fifteenth century and a late fifteenth-century altarpiece—possibly of north German or Swedish workmanship—reflect the church's medieval devotional life, while a rococo pulpit was made in 1777 by Lars Scherling. The churchyard contains a free-standing eighteenth-century bell tower, and three lychgates are set into the surrounding churchyard wall.
The church has had several organs over the centuries, and the surviving case front on the present instrument dates from the 1890s, though the mechanism itself was renewed in the mid-twentieth century.