The church stands on a site with a long history of settlement: archaeological finds in the surrounding area suggest Glanshammar was once an important cult, assembly and market place in the region, and it is thought a wooden Viking-era church may have stood here as early as the 11th century. Nothing of that timber building survives above ground, but its memory lingers in the runestones now associated with the site.
The present stone church dates from the 1100s and retains its original tower from that period. During the Middle Ages a chancel and a north aisle were added, and in 1678–1679 a burial chapel was built for the Reuter family. The building therefore shows the layered growth typical of many Swedish parish churches, spanning several centuries of alteration.
The most striking feature for visitors is the well-preserved ceiling and wall painting scheme of 1589, attributed to Anders Jordansson Ryttare of Närke. On the south wall a few fragments of earlier medieval decoration also survive, including a depiction of Adam as a ploughman, offering a rare glimpse of the church's original 12th-century decorative scheme beneath the later work.
Glanshammar is also notable for its runestones: of the twenty-nine known runestones in the province of Närke, no fewer than eight have been found in or near the church. Some are built into the church walls, one forms part of the paving near the sacristy entrance, and others have been transferred to Örebro County Museum. One stone, catalogued as Nä 28, is recorded from an early seventeenth-century drawing and is said to commemorate a father raised in memory by his son, though the stone's exact present location near the entrance is not entirely certain from the sources.
Inside, visitors can see several medieval sculptures, including a depiction of Saint Bridget, along with a medieval font. The altarpiece was carved by the sculptor Gabriel Beutin of Stockholm and donated by Gustaf Reuter the Younger in 1727, while the present altar, made of local marble, was consecrated in 1977. The church's pneumatic organ, built in 1951 by Olof Hammarberg of Gothenburg, replaced several earlier instruments dating back to 1703.