Schloss Petronell, Baroque castle in Petronell-Carnuntum, Austria.

Schloss Petronell is a three-storey, four-winged early Baroque castle built from 1660 to 1667 by Domenico Carlone for the Abensperg-Traun family in Petronell-Carnuntum, Lower Austria. Its pale stone facades with red tiled roofs enclose a large courtyard, entered across a stone bridge through a Baroque portal. The courtyard front, painted pink, grey and yellow, has an external staircase beneath a clock tower with a conical roof, leading to a 360 m² festival hall.

The castle was built between 1660 and 1667 by the architect Dominico Carlone for the Abensperg-Traun family. The same family held the property for seventeen generations before it changed hands in 2006.

The village name comes from Saint Petronilla: Agnes of Poitou, widow of Emperor Henry III, gave the settlement as a fief to Count Rapoto V of Vohburg, and the Petronilla church was dedicated to her patron saint. The castle's Golden Ancestral Hall held the Petronell Willkomm, a glass goblet of about 1480 from which Emperor Matthias drank in 1613; it was given to the Kunsthistorisches Museum in Vienna in 1999.

The castle is currently being converted into a hotel, so the interior and grounds are not open to visitors. The exterior can be seen from the street, and the site is easy to combine with a visit to the nearby Roman ruins.

In 1613 Emperor Matthias visited Petronell and drank a welcome toast from the Petronell Willkhumb, a glass goblet made around 1480. The cup stood in the ancestral hall until 1999, when it was given to the Kunsthistorisches Museum in Vienna.