Kloster Diesdorf, Romanesque monastery in Diesdorf, Germany.

Kloster Diesdorf is a former Augustinian choir-nuns' foundation whose church, St. Maria und Crucis, was built from 1182 to 1230 by Jerichow masters in late Romanesque style from brick. It is a three-nave basilica with transept, choir and apses under a steep red tiled roof; the square west tower with its pointed dark roof and round-arched windows was added in 1872 in Neo-Romanesque style. A pointed-arch portal sits at the base of the tower, and a half-timbered building with white plaster panels stands in front.

Founded in 1161 by Count Hermann of Lüchow, it initially housed both Augustinian canons and choir women. Over time it evolved into an exclusively female community, reflecting changing patterns of monastic life in the region.

The monastery began as a house of Augustinian choir women, often unmarried members of the founding Lüchow family; a double monastery with canons is presumed but undocumented. By 1551 it became a Protestant ladies' foundation where a Domina, seven noble and six bourgeois ladies lived in their own houses. The south gallery later added for the congregation contrasts with the north gallery used by the choir women for the hours.

The church stands on the Romanesque Road and is still Diesdorf's parish church, so visits are usually possible outside service times. The surviving medieval monastic outbuildings and long stretches of the cloister wall stand nearby and can be seen from the outside. In the brickwork of the north transept the passage from the dormitory to the nuns' gallery is still recognisable.

The Heilig-Grab-Kapelle in the north aisle was first mentioned in 1332, and the brickwork of the church still shows where the convent buildings joined it: on the north transept the passage from the dormitory to the nuns' gallery can be traced. The west tower was added only in 1872 in neo-Romanesque style, after the roof turret over the choir was demolished in 1827 and the bells moved into the tower.