According to an old document kept in the church, Gumlösa kyrka was consecrated on 26 October 1191 by Archbishop Absalon of Lund, reportedly with Norway's Archbishop Eirik Ivarsson and Bishop Stenar of Växjö also present, though the exact dating is treated as somewhat uncertain. The brick used to build it is thought to have been fired close to the site itself, an early and technically notable achievement for the period.
The church's patron, Trugot Kettilsson, is said to have donated a collection of relics at the consecration, reputedly including a strand of hair attributed to the Virgin Mary and a fragment said to be from the True Cross; an old inventory list even suggests the church once held as many as 96 relics. Such claims about medieval relics cannot be verified and should be read as tradition rather than established fact.
Unusually for a church of this age, Gumlösa was built from the outset with both vaulting and a tower. Its hilltop position overlooking a ford across the Almaån river, together with high-set windows and holes beside the doors possibly used for defensive beams, has led to suggestions that the building also served a defensive function. The upper part of the tower and the stepped gables were altered later in the medieval period. The exterior brickwork appears never to have been rendered, while internal plaster was removed in the late nineteenth century to expose the red brick beneath.
A fire in 1904 devastated the church, destroying almost all its furnishings and leaving only the walls and the massive vaults standing. The subsequent careful restoration, based on drawings by Theodor Wåhlin, gave the church its current Romanesque-style windows and doorways. An unused gravestone depicting Birger Nilsson (Grip) and his wife Brita Joakimsdotter Brahe can be seen on one of the church's walls.
The sandstone font is essentially the only furnishing to have survived the 1904 fire, and it is thought to be as old as the church itself, possibly present at the original consecration. It is signed by a stonemason named Tove, a notable rarity for medieval church fonts. The church's organ, built in 1857, was destroyed in the same fire; the present instrument dates from 1906.