Located on the first floor of the Petit Château in the Renaissance wing, the Grands Appartements comprise three rooms decorated in 19th century style, standing over the old water ditch separating the two château buildings, and the apartment of the Princes de Condé (17th - 18th century).

• The Antechamber

Both this room and the Salle des Gardes date from the 19th century. They were built by Honoré Daumet to link the Grand Château to the Petit Château, which up till then were separated by a moat spanned by a covered bridge. During the French Revolution, the château was emptied of its collections (furniture and paintings), but the antechamber has several reminders of how Chantilly was decorated in the 18th century, such as the two paintings by Jean Baptiste Oudry or the mineralogical cabinet by Haupt.

• The Salle des Gardes (the Guardroom)

Le comte de Berghe, portrait by Van Dyck.

• The Prince's chambers.

The wood panelling in this room was produced under the supervision of Jean Aubert around 1720 for the Duc de Bourbon (1692 - 1740), a minister of Louis XV and the person responsible for building the Grandes Ecuries.
The large chest of drawers in Riesener marquetry, with gilded and embossed bronzes by Hervieu, was commissioned by King Louis XVI for his chambers in Versailles.

• Cabinet d'Angle (The Angle Room)

This angle room was part of the apartments of the Prince du Condé, decorated around 1720. The white and gold wood panelling, decorated with hunting scenes, are characteristic of the 18th century. The Jean Baptiste Sené furnishings (18th century), covered in Beauvais tapestries, belonged to the Comte de Provence, brother of King Louis XVI.

• Grande Singerie (The Monkey Room)

A charming boudoir dating from 1737, previously attributed to Watteau and entirely decorated with wall paintings by Christoph Huet, the Grande Singerie is covered in representations of monkeys and grotesque Chinese figures, typical of the period. Sitting rooms decorated with monkeys, apes and Chinese figures were fairly commonplace in mansion houses in the 18th century.

• The Galerie des Actions de M. Le Prince (The Prince's Battle Gallery)

Le Grand Condé commissioned the painter Sauveur Le Conte, a pupil of Van der Meulen and a specialist in military scenes, to paint eleven paintings representing his principal military actions and gave precise instructions on how they should be executed. He died in 1686, although the work, which lasted from 1686 to 1692, had by then hardly begun.

• The Salon de Musique (The Music Room)

The Salon de Musique contains souvenirs of the young Duc d'Enghien and Jacob furniture from the Salon des Jeux in Saint Cloud.