La Stanza Gialla
The "Yellow Room" is similar in plan and measurements to the "Room of the Columns" and is similarly covered by a segmental barrel vault. It differs from the former only by its painted decorations, which here are on a dark-yellow background.

The room is accessed through a wide opening; the travertine threshold still bears round cuttings for the door jambs. Traces of white stucco, now visible only inside the lightwell above the doorway, suggest that in an earlier phase the walls of the room were painted in solid white.

A short socle, composed of thin marble slabs of various colors running along the base of the four walls, protected the paintings and improved the overall decor.

A concrete pilaster rests against one wall: it was built, probably in the Trajanic period, to support the upper storey of the domus that at the time must have expanded.

With the exception of the part damaged by the construction of the Trajanic pilaster, the paintings, which are now regularly monitored and maintained, have survived in exceptional integrity. Similarly to the "Room of the Columns", the decorations belong to a particular sub-group of the 4th Pompeian style characterized by the subdivision of the wall surface in three horizontal panels: a socle at the bottom (podium), a tall middle panel, and a cornice at the top.

The very deteriorated socle was originally decorated with vertical and horizontal painted bands in dark red. A similar pattern is repeated by the frames of the panel above (probably painted in a later phase) that enclose representations of aediculae and perspective vistas. Inside the aediculae, miniature seascapes are rendered in the form of small tableaux (pinakes). Natural elements and decorative objects (imaginary figures, candelabra, spirals, and festoons) that hang from or rest on top of the stylized buildings, break the otherwise very orthogonal composition.

Some painted ornamental objects celebrated the sophistication of the house owner: masks symbolized theatrical performances and reminded of Dionysiac cults; vessels and candelabra were a direct reference to the expensive possessions of the patron; animal heads, panoplies, and shields recreated the atmospheres of temples and shrines. Finally, the many animals, real and fictional, placed the painted scenes in an idyllic and dream-like world.

The ceiling is decorated with a painted reticulate pattern of light-blue squares intersecting yellow circles. At the corners of each square, small circles frame miniature representations of fictional creatures, now only faintly visible.
The floor is made of white and black stone fragments inserted in a layer of cocciopesto; the threshold is instead made of various pieces of colored marble.