Haller Mansion, Renaissance castle in Sânpaul, Romania.

Haller Mansion is a Baroque castle built in 1760 by Gábor Haller, grandson of János Haller. Its U-shaped wings and courtyard arcades follow the model of the Grassalkovich castle in Gödöllő, as Gábor's wife Anna-Mária Grassalkovich was the builder's daughter. The main façade has a projecting central bay with a mansard roof, while the courtyard side shows arcaded ground-floor openings and shuttered windows.

A first castle built here by Ferenc Alárdi in the 16th century was destroyed after the 1575 Battle of Kerelőszentpál. In 1609 Prince Gabriel Báthory donated the estate to István Haller and his brothers; István began a new castle, finished in 1674 by his son János. Destroyed again during the Rákóczi wars, it was replaced by the present Baroque mansion, built in 1760 by Gábor Haller.

The castle bears the name of the Haller family, who owned Sânpaul and the estate for 339 years. The family was Roman Catholic, and its two main branches descended from the sons of Gábor Haller (1550–1602). The ornamental garden was created by Countess Ilona Bethlen, who planted the roughly 50-hectare grounds in the early 1900s.

The castle stands in Sânpaul, Mureș County, 19 km southwest of Târgu Mureș on the left bank of the Mureș, beside the Cluj–Târgu Mureș road. The building is in a very dilapidated state and its future looks uncertain, so visits should be planned with that in mind. It was repaired in 1959–1960 and later used as an agricultural centre, a school and a vegetable store.

The Haller family, of Nuremberg origin, held Sânpaul and its castle for 339 years after Prince Gabriel Báthory donated the estate to István Haller and his brothers György and Zsigmond in 1609. The family received the baronial title in 1699 and the comital title in 1713. The last owners before nationalisation were Count István Haller and his wife, Baroness Maria Luise Schell Bauschlott.