The oldest parts of the building date to the 1200s, when a rectangular hall church stood on the site. Sections of its original walls survive in the present east and west walls and the south nave wall, giving the church a genuinely medieval core beneath later rebuilding.
The church's present cross-shaped plan is largely the result of eighteenth-century work. In 1704 the north wall was removed, the nave narrowed, and a north transept added, with the sacristy enlarged at the same time. A south transept followed in 1758, and in 1767 the sturdy west tower, topped with a curved lantern-crowned cupola, was built by master builder Petter Frimodig. The transepts are notably wider than the nave and chancel, giving the interior an unusual proportion, and the wooden barrel vaults date from the 1750s.
A restoration in 1956–57 by Erik Lundberg deliberately reintroduced medieval character to the interior: an oak crucifix from the mid-1300s, made in Östergötland, was returned to its position on the triumphal arch, medieval wall paintings from the later 1400s were uncovered, and the transepts were visually shortened within the church space. A burial chapel was also fitted into the room beneath the north gallery.
Other notable furnishings include a brass font from the later 1600s and a former altarpiece painted by Pehr Hörberg in 1806. Musically, the church is of particular interest to organ enthusiasts: alongside a larger organ built by Olof Hammarberg in 1926 and later reworked, it houses a rare small positive organ originally built by Isac Risberg, an organ builder linked to the workshop of Hans Henrich Cahman, whose work included the organ interior at Uppsala Cathedral after its 1702 fire. Bought for Tjällmo in 1739, the Risberg positive was restored in the late 1960s in an effort to return it close to its historical state, and today is tuned in meantone temperament, a detail of interest to specialists in historic organs.