Frasne-le-Chateau castle is situated on the east side of the village. It lays on the foundations of a medieval castle previously surrounded by a ditch, which was fed by a stream flowing not far from there: the Jouanne.

The land and the castle have been Oisèlay’s property since the 13th century. Probably, in the 15th century some great works were made on the castle, which was provided with a tower on the west side, today’s main entrance and a cross vault hall on the south-east side. It was probably Antoine d’Oisèlay the one who transformed again the castle at the end of the 16th century and built the north facade. In 1582 he married the niece of the cardinal de Granvelle, who was the ambassador of Prague’s emperor. The castle shows many emblematic signs - dated 19th century - suggesting Granvelle’s prestige.

Subsequently, the castle  goes to the La Baune Saint-Amour family. In 1708 it is sold to  Jean-Claude and Jean-Baptiste Rochet. It is later handed on to Fraguier de Batilly. During the 8th year the land and the castle were sold to Francois Gabriel Henrion. Between 1835 and 1891 his son, Cesaire Emmanuel Flavien Henrion de Magnoncourt, started some major works, entrusted to Pierre Marnotte. These works gave the castle its present aspect, although some other changes were to be made, especially to the park.

The north-east bending wing was therefore rebuilt in the place of the north one, together with the attic facade. The whole of the inner partitions and decorations are dated this period.

Frasne castle has got a U-plan, in which the west wing acts as entrance. The 15th century tower and the north-east wing (rebuilt by Pierre Marnot) have the same setting as the main building one: upon the gallery, under a three-centered arches vault, there is a series of mullioned windows with pediments and a shells-adorned attic. The frequency of the vertical girders is strengthened by some ionic pillars on decorated bases placed to the right of the ground level pillars. It is also horizontally balanced by the repetition of the prominent cornices.

On the inside there are some probing elements from the 19th century: plasterworks and fireplaces, parquet floors, round rooms with paneled parquet floors and the “all’italiana” library, with vertical lighting, covered by neo-Gothic painted decorations. The library was transformed into the chapel of the “Congregation of the Divine Providence” sisters from Ribeauvillé, who used the castle as a pension, a rest home and a school until 1991.

To this day some renovation works to the facade and the medieval tower are expected to be made.