The church's name derives from the Old Swedish 'Drotin', meaning Lord or God, and medieval sources refer to it in Latin as S:t Trinitatis and in Swedish as S:t Drotten - a dedication to the Holy Trinity. Trefoil blind arcading on the east and west gables, an ancient symbol of the Trinity, is thought to reflect this original naming, though a later inscription and an eighteenth-century church bell instead call it S. Dorothae, possibly an adaptation for an international readership. Archaeological work has found older graves beneath the present building, suggesting an earlier timber church, possibly of stave-church type, once stood nearby.
The church was built from rubble stone in a rural building tradition, in contrast to the brick technique used in the town's own St Laurentii church. Its oldest surviving part is the brick-built sacristy, raised as a separate chapel around the late 1200s, with the main church added onto and above it soon after; Drothems kyrka is first documented in 1307. Difficult ground conditions - a deep layer of clay beneath the site - caused structural problems from an early stage, and cracking in the vaults eventually led to major foundation strengthening works in 1979-80.
To stabilise the building, an early repair in the 1300s introduced the distinctive angled wall supporting the chancel arch, still visible today, along with buttresses at several corners. The church suffered damage during the Danish commander Daniel Rantzau's capture of Söderköping in 1567, reportedly standing roofless for some years before being restored with royal and national support. A tall spire shown in Erik Dahlberg's late seventeenth-century engraving was later removed after storm and structural damage, and the roof was subsequently covered in slate.
Inside, an oak altarpiece attributed to a Lübeck workshop of the late 1400s and a limestone font from a Gotland workshop, also from the 1200s, are among the church's notable medieval furnishings, alongside a wooden crucifix and figures from the same era. A pulpit dates from 1704. Fragments of medieval paintwork, including traces near the site of an old Marian altar, were uncovered beneath later whitewashing, though their original subject cannot now be identified.
The church has been reordered and repaired repeatedly over the centuries, with major changes to windows, pews and plasterwork in the 1800s, and further structural reinforcement in the 1950s and 1979-80. Its organ has been rebuilt and replaced several times, most recently in 2023-24.