Lambertikapelle, Medieval chapel in Werben, Germany.

The Lambertikapelle is a plain rectangular brick building from the early 13th century in Werben, southwest of St. Johannis Church. Its gables carry the Johanniter cross, and it has Romanesque round arches alongside an early Gothic pointed arch in the blocked window on the southern east wall. Recent research questions whether it ever served as a chapel and suggests it may have been the residence of a high-ranking member of the Order of St. John.

Built in the first half of the 13th century, the brick building is the oldest evidence of the Knights Hospitaller's construction activity in Werben. Their commandery initially oversaw Saxony, the Mark Brandenburg, Pomerania and the Wendland, and later became the administrative centre of the Brandenburg bailiwick. After the Templar order was dissolved in 1312, a papal decree gave the Hospitallers Templar lands; the Treaty of Kremmen left them one third, enough to found a bailiwick. The building has been restored in sections since 2020.

The building's name comes from the Dehio handbook, which calls it a former Lamberti chapel of the Johanniter commandery, though recent research doubts it ever served as a church and suggests it may have housed a high-ranking member of the order. The Johanniter cross in the gables marks the order's presence in Werben.

The brick building stands southwest of St. Johannis Church in Werben and is not open to the public; visitors view the exterior with its Johanniter crosses in the gables. Since 2020 it has been renovated in sections, so scaffolding may cover parts of the facade.

The building is brick, not stone, and its gables carry the Johanniter cross of the Order of St. John. Recent research questions whether it was ever a chapel at all: it may have been the residence of a high-ranking member of the order. Since 2020 it has been renovated in stages.