The so-called Queen's Room, which was intended for Doa Mara Amalia of Saxony, the wife of Charles III, but was never filled because she passed away in 1760, four years before the Palace was inhabited, is divided into three chambers that make up this remarkable area. The architect José Segundo de Lema carried out the King Alfonso XII's request to connect the three dining rooms for formal celebrations, and it was launched in 1879 with the grand supper of the King's second marriage to Mara Cristina de Habsburgo-Lorena.

The columns used in the vault adornment are constructed of Bagnères marble, and the majority of the bronze ornamentation—including the fifteen chandeliers and ten sconces—was produced in Paris. These fixtures now have LED lighting, which improves visibility without endangering any of the displayed works of art. Up to 144 persons may sit around the table.

The Vertumnus and Pomona series of tapestries by the 16th-century Belgian craftsman Willem Pannemaker adorn the walls. The walls and balcony openings are respectively decorated with six enormous bronze and porcelain vases by Sèvres (1826-1830) and gigantic 18th-century Chinese porcelain tibores. The vaults were painted, the first by Mengs (The Dawn in his chariot), the second by Antonio González Velázquez (Christopher Columbus before the Catholic Monarchs after the discovery of America), and the third by Francisco Bayeu (Surrender of Granada), and they correspond to the three in the prehistoric halls.