Château de Couëllan, Heritage listed castle in Guitté, France.

Château de Couëllan is a country manor in Brittany built with granite and schist stone. The western gable wall still bears traces of original plaster, showing how the building once appeared.

A 15th-century manor of the l'Hermine family passed by marriage to the Boisjean family and was badly damaged during the Wars of the League. The present château was built around 1620 for Simon Hay des Nétumières, who had married Madeleine du Boisjean, heiress of Couëllan, in 1603. The main body, left unfinished, was completed and extended north between 1775 and 1777 for the Saint-Pern family. The façades and roofs were listed as monuments historiques on 24 February 1976.

The name Couëllan comes from the l'Hermine family's manor, passed by marriage to Madeleine du Boisjean, heiress of Couëllan, who wed Simon Hay des Nétumières in 1603. The Saint-Pern family, who finished the main wing between 1775 and 1777, later moved the iron gate from their Château du Lattay at Guenroc to the entrance of the Couëllan woods in 1929.

The castle stands in Guitté, in the Côtes-d'Armor department of Brittany. The 1836 cadastre shows the main courtyard closed at the south end of the outbuildings by a wall joining the chapel, now isolated. The former main courtyard became a landscaped park in the late 19th century, and the south enclosure wall was demolished.

The 17th-century staircase is built of wood rather than stone, suspended in a wide cage lit on three sides, and keeps its original wrought-iron railing with repoussé sheet-metal ornaments from the start of Louis XVI's reign.