Royce Hall is a building on the campus of the University of California, Los Angeles (UCLA). Designed by the Los Angeles firm of Allison & Allison (James Edward Allison, 1870–1955, and his brother David Clark Allison, 1881–1962) and completed in 1929, it is one of the four original buildings on UCLA's Westwood campus and has come to be the defining image of the university. The brick and tile building is in the Lombard Romanesque style, and once functioned as the main classroom facility of the university and symbolized its academic and cultural aspirations. Today, the twin-towered front remains the best known UCLA landmark. The 1800-seat auditorium was designed for speech acoustics and not for music; by 1982 it emerged from successive remodelings as a regionally important concert hall and main performing arts facility of the university.

Named after Josiah Royce, a California-born philosopher who received his bachelor's degree from UC Berkeley in 1875, the building's exterior is composed of elements borrowed from numerous northern Italian sources. While very different in their composition and near-symmetry, the two towers of Royce make an abstract reference to those of the famous Abbey Church of Sant'Ambrogio in Milan. A building of very similar form on a much smaller scale was a centerpiece of the College of California campus in Oakland in 1860, the predecessor of the University of California.

Severely damaged in the 1994 Northridge earthquake, Royce Hall underwent a $70.5 million seismic renovation. Designed by architects Barton Phelps & Associates and Anshen + Allen Los Angeles and completed in 1998, the project combined structural strengthening and functional improvements with extensive interior updating. The iconic towers were strengthened and restored on an emergency basis. The project for the 200,000 square foot building itself inserted a new, six-story structural system of concrete panels located in the auditorium walls and connected by concrete beams to the building's historic exterior brickwork. Eligibility for National Register listing prompted FEMA earthquake resistance requirements well beyond normal safety levels and triggered close design scrutiny by preservation officers. The new "soft" structure is designed to respond in unison with original masonry infill to provide maximum earthquake resistance and protect the building's historic fabric from damage.

The sidewalls of the auditorium were reconfigured to incorporate foot-thick concrete shear panels, the volume of which may have reduced its reverberant character. New wall openings, cut into previously unused rooftop areaways, were enclosed with new structures to create operable acoustic galleries that allow for adjustable acoustic responses.

Together with new ceiling coves, these galleries increase the hall’s volume by 40,000 cubic feet and extend its reverberation time by more than one second at maximum setting. Skylights within the galleries restore natural light to the coffered ceiling, which is now illuminated for the first time.

Unlike the former plaster interior, the new walls are clad in brick and terra cotta matching the building’s original exterior. The uneven texture of the projecting blocks enhances sound diffusion, with patterns inspired by Lombard Romanesque motifs found in Lucca and other cities of the Po River valley in northern Italy.

The hall, post renovation, covered 191,547 square feet (17,795.3 m²).

The hall contains a 6,600-pipe E.M. Skinner pipe organ, renovated and expanded in 1999 by Robert Turner. During the 1930s, Salt Lake Tabernacle organist Alexander Schreiner gave public recitals three times a week on the instrument. The organ was later featured in several recording sessions of the Los Angeles Philharmonic under Zubin Mehta. It serves as one of the home venues for the Los Angeles Chamber Orchestra. Luminaries who have appeared on its stage include musicians George Gershwin, Leonard Bernstein, and Ella Fitzgerald, and speakers Albert Einstein and John F. Kennedy.^{[citation needed]}