Munsterbilzen Abbey was an abbey of Benedictine nuns in Munsterbilzen, Limburg, Belgium, founded in around 670 by Saint Landrada. It was plundered by Vikings in 881 but restored. From the 9th century it was dedicated to Saint Amor.
It was an imperial abbey of the Holy Roman Empire separately administered from the surrounding County of Loon. The abbess exercised lordship over the village of Munsterbilzen and four more villages nearby until 1773, when she was forced to recognize the suzerainty of the Prince-Bishop of Liège. The abbey was dissolved and its property confiscated at the time of the French Revolution.
Dating back to the time of the Merovingian dynasty, it is considered the oldest women's convent in the Greater Netherlands, and, together with the abbey of Sint-Truiden, the abbey of Aldeneik, the abbey of Susteren, and the abbey Rolduc, one of the most important monasteries in the Dutch-speaking part of the diocese of Liège.