The church was built just outside the walls of its medieval predecessor, which was demolished piece by piece as the new building took shape, a common practice that allowed worship to continue with minimal interruption. Constructed of grey stone and brick, the church has a tower and a semicircular sacristy; the tower may incorporate remnants of the older church, though it appears to have been completed later in the nineteenth century.
Spjutstorp was historically what is known as a patronage church (patronatskyrka), a system abolished in Sweden only in 1922. Under this arrangement the owner of the nearby Kåseholm estate collected tithes from parishioners but was also responsible for maintaining the church and appointing and paying its priest and sexton. The patron behind the new building was Johan Peter Hintze of Kåseholm, who also sponsored the neighbouring church at Tryde, designed by Edvard von Rothstein; it is thought the same designs may have been reused at Spjutstorp, though this is not certain.
The altarpiece, depicting the Resurrection of Christ, survived from the earlier church and is attributed to the noted court painter Pehr Hörberg. Born in 1746 to a poor soldier's family in southern Småland, Hörberg rose from humble origins to study at the Royal Academy of Art in Stockholm and eventually became a royal court painter, decorating many churches, particularly in Östergötland. According to local tradition the painting arrived at Spjutstorp in 1790 after previously hanging in a church in Gothenburg, though this account cannot be independently confirmed. The pulpit is said to have been made in Gothenburg around the same time.
Other notable furnishings include a sandstone font probably dating from the 13th century, a brass christening basin from the late 17th century decorated with a depiction of Christ's baptism (once exhibited at the Baltic Exhibition in Malmö in 1914), and an alms box dated 1438 that came from the old church and now stands by the main entrance. The tower holds two bells, the larger cast in 1438 and the smaller in 1801. A woven tapestry, the Tree of Life, was made by textile artist Inga Mittendorf and donated by the church's needlework circle.
One unusual survival is a richly carved wooden bier, or catafalque, more than 300 years old and decorated with carved figures including a skull and four apostles, with leather covering and inscribed text along its sides. It was rediscovered during an inventory when the parish mortuary was being closed, having been mistaken at first for a pile of old boards; it is now displayed inside the church. The current organ was built in 1956 for Ullstorps kyrka and moved to Spjutstorp in the late 1960s.