Usine de Pierrefonds, Sugar refinery in Saint-Pierre, Réunion Island, France.

Usine de Pierrefonds is a sugar refinery in Saint-Pierre, Reunion Island, consisting of multiple interconnected buildings including a T-shaped production hall and a northeastern distillery structure. The complex displays the characteristic architecture of sugar processing, with spacious buildings designed to handle large-scale cane milling and processing operations.

The facility was founded in 1834 and became one of the major sugar processing plants on the island. It played a significant role in the industrialization of Reunion and operated for over 130 years before closing in 1970.

The site is named after the Pierrefonds district of Saint-Pierre, and its land and buildings were listed together as a supplementary historic monument on 22 October 1998. In 2022 the Mission Patrimoine selected it for the loto du patrimoine, the national lottery funding endangered heritage. Visitors see this selection reflected in the site's current status as a protected, disused sugar refinery awaiting reuse.

The complex is a derelict ruin with no visitor facilities; access to the buildings is not arranged and the structures are unsafe to enter. The site lies at Pierrefonds in Saint-Pierre, near the Saint-Etienne Canal, and can be viewed from the surrounding public ground. Visit in daylight and keep to the outside of the perimeter.

The site was selected in 2022 by the Mission patrimoine for the loto du patrimoine, the national lottery that funds endangered heritage. Its entire grounds, not just the buildings, were inscribed on the supplementary inventory of Historic Monuments on 22 October 1998. The tall rusted lattice crane and the dark grey stone chimney are the landmarks visible from outside.