Seeon Abbey, Benedictine monastery in Seeon-Seebruck, Germany

Seeon Abbey is a former Benedictine monastery on an island in the Seeoner See, in the municipality of Seeon-Seebruck north of the Chiemsee. Its centre is the parish church of St. Lambert, a Romanesque basilica vaulted in the late Gothic style around 1428–1433, with two towers carrying copper onion domes added after a fire in 1561. The connected white-walled wings with red pitched roofs enclose an inner courtyard with paths and green spaces.

The abbey was founded in 994 by Pfalzgraf Aribo I of Bavaria and housed a significant scriptorium producing manuscripts for religious institutions. After centuries as an active monastery, it transformed into a cultural and educational center in 1993.

The abbey's name comes from the lake, the Seeoner See, on whose island it stands. Its church, dedicated to St. Lambert, holds Renaissance frescoes of 1579 that show Saints Benedict and Lambert beside the founders Aribo and Adala. Since 2017 the CSU parliamentary group has held its annual retreat here, receiving guests such as Erna Solberg and Vitali Klitschko.

The island is reached by a causeway built after the abbey was dissolved in 1803; there is no ferry. The former monastery now operates as a conference hotel with 92 rooms and 16 meeting rooms, so some areas may be busy during events. The restored cloister and the parish church of St. Lambert are open to visitors.

The founder's tomb in the castle chapel is the Stifterhochgrab of Pfalzgraf Aribo I, carved by Hans Heider around 1400; the red marble gravestone of Abbot Honoratus Kolb, who led the abbey from 1634 to 1652, is a separate work. Along the chapel walls stand the gravestones of 15th- and 16th-century abbots.