The Château de Saissac is a ruined Cathar castle in the southernmost tip of the commune of Saissac in the Aude département in the north-west of Carcassonne, France. It was once the residence of the powerful vassal family of Trencavel. Today the ruins are protected as official historical monuments of France (French: monument historique).
The castle domiates the rocky headland and the ravine of Vernassonne, at an important strategic position at the entry of the Montagne noire. Based on historical texts, it can be dated back to at least 960. It was bequeathed by the bishop of Toulouse to the Count of Carcassonne. In the 11th century, the castle was pledged to powerful vassals in the country.
They formed a junior branch under the counts of Foix who formed at the time the lineage of Saissac. It is important all the same to note the presence of a castrum under the current caste, probably dating from the 11th century, though its origin can go back to the time of the Visigoths.
At the end of the 13th century, the castle became the inheritance of the family of Lévis, new lords of Mirepoix. From 1331 to 1412, it passed to the family of Isle-Jourdain. In the 15th century, the barony was held by the family of Caraman. The castle changed hands repeatedly until 1565, passing through the hands of Bernuy, a rich man, and house of Clermont-Lodève.