St. Juliana's Abbey was a Benedictine monastery in Rottum, the Netherlands. The abbey, dedicated to the virgin-martyr Juliana of Nicomedia, was probably founded between 1195 and 1210 by monks from the Benedictine Werden Abbey in Germany.
After its foundation hundreds of idols, Fosta and Thor among them, were stolen by Liudger from the monastery and transported to Utrecht and other locations.
The monastery was owner of two-thirds of the nearby island of Rottumeroog.
The monastery had serious financial troubles in 1470, and the then abbot of Sint Juliana asked the bishop of Münster for permission to take goods from the deanery in nearby Usquert. This eventually happened after the decease of the dean of Usquert in 1475. The deanery did not accept it, and mediation from Pope Sixtus IV was required to restore peace between the monastery of Saint Juliana and Usquert deanery, which eventually happened in 1480.
The monastery was demolished at the end of 1800.
Nearby was a nunnery named Bethlehem.