Kloster Neuendorf, Cistercian nunnery in Gardelegen, Saxony-Anhalt, Germany

Kloster Neuendorf is a Cistercian monastery near Gardelegen featuring a brick church, low cloisters, and associated monastic buildings. The church's stained glass windows date from different centuries and display various craftsmanship techniques.

The monastery was founded in 1228 as a Cistercian convent and became one of the wealthiest female monasteries in the Altmark region. Its importance grew through close connections with the Alvensleben family, who served as patrons and protectors.

The village and the former monastery share the name Neuendorf, recorded in 1232 as Niendorp. The church, dedicated to Mary, Benedict and Bernard, is now the parish church of the Evangelical Lutheran congregation and occasionally hosts concerts. The former malt and brewhouse south of the church, built in 1860, and the 1561 building called "Hundeloch", once a prison and grain store, stand nearby.

The monastery lies in the village of Kloster Neuendorf, north of Gardelegen in Saxony-Anhalt. The church is used as the Protestant parish church, and concerts are held there occasionally. The former cloister buildings stand west of the church; the south wing now serves as the parsonage, and a seven-bay cloister walk is preserved on its north side.

The oldest gravestone in the church dates from 1320, and around 1403 the widow Berta von Alvensleben donated a silver-gilt communion chalice that is still kept there. The church also holds eight medieval stained-glass windows made in the 14th and 15th centuries, the oldest from 1360.