The Anteroom is a modestly decorated apartment of irregular shape, with a mezzanine designed for the use of service personnel on duty. In its decor and furnishings, the room is not unlike the interiors of country mansions of the early nineteenth century. The walls are adorned with canvases by Western European landscape painters of the seventeenth to nineteenth centuries. The furniture, mainly of the Jacob type, includes several beautiful pieces from the workshop of Heinrich Gambs: a secretaire and two commodes of mahogany with chased bronze decorations; the large bureau is an early work of Gambs, done in the manner of David Roentgen, his teacher.

The elegant set of mahogany chairs and armchairs with carved and gilded figures of swans is attributed to Voronikhin. Most of the late eighteenth-century watercolours and gouaches that adorn the walls are the work of Semion Shchedrin and Andrey Martynov. They show views of the parks at Pavlovsk, Gatchina and Tsarskoye Selo, and thus provide invaluable information for the historians of these palace and-park complexes.

The Anteroom links the apartments of the central building with those of the southern suite. Initially their architectural and decorative scheme was designed by Vincenzo Brenna; and the first room of the suite, The Round Room, has retained his decor: the moulded door ornaments with lion masks, the cornices, the ceiling painted in imitation of a coffered vault, etc. All the other rooms of the suite, remarkable examples' of early nineteenth-century palace interiors, were decorated by Giacomo Quarenghi and Andrey Voronikhin.