A church is thought to have existed at Hjärnarp since the 1100s, a rectangular building with a west tower, originally separated from the nave by a wall. Over time this medieval church fell into disrepair and became too small for the growing parish; by the 1830s inspectors found serious cracks in its walls and vaulting, and services were moved temporarily to the neighbouring Tåstarp church. Little of its furnishings survive, though it is said to have resembled Tåstarps kyrka in appearance.
The present stone church was built between 1838 and 1843 to a neoclassical design by the architect Carl Stål, and was taken into use on Candlemas Day, 4 February 1844. Its construction proved troublesome: the building contract had been awarded to the lowest bidder, a common but problematic practice in this period, and when the builder later went bankrupt the parish itself had to cover the cost of repairs, needed as early as 1847. Numerous further repairs and alterations followed over the following century.
Several older furnishings were carried over from the medieval church, including a sandstone font from around 1200 with a brass basin from the 1600s, an offertory chest from the 1780s, and older church silver. The larger of the two bells was recast in 1868 from an earlier bell, while the smaller was cast in 1867.
The most striking feature today is the large fresco covering the chancel wall, begun in 1947 by the artist Pär Siegård and largely completed, due to his illness, by his close collaborator Nils Möller under Siegård's continued direction; it was completed and dedicated in 1957. Covering around 100 square metres and containing some sixty figures, it depicts scenes from the Passion of Christ, from the entry into Jerusalem through to the Crucifixion and Resurrection, with a local touch in the use of a Scanian rag rug motif in the Jerusalem scene. Nils Möller also created a stained-glass window above the south door, gifted in 1985, while another window above the north side, symbolising the cross, was moved from the chancel and was a gift from a local sewing circle.
Other notable items include a wooden Madonna and Child by Erik Tanis near the font, ceramic urns by Gustav Kraitz, a woven textile from Märta Måås-Fjetterström's studio in Båstad, and three chandeliers donated by local benefactors between 1897 and 1917. In the churchyard stands a small chapel dedicated to St Stephen, built in 2008, along with the grave of the trumpeter Arne Lamberth, whose headstone bears the image of a trumpet.