The Juilliard String Quartet is a classical music string quartet founded in 1946 at the Juilliard School in New York. The original members were violinists Robert Mann and Robert Koff, violist Raphael Hillyer, and cellist Arthur Winograd; Former second violinist, later first after Mann's retirement, Joel Smirnoff left the quartet after its 2008-2009 season to become president of the Cleveland Institute of Music. Since the Quartet's inception in 1946, it has been the quartet-in-residence at the Juilliard School. It has received numerous awards, including four Grammys and membership in the National Academy Recording Arts and Sciences’ Hall of Fame. In February 2011, the Juilliard Quartet received the NARAS Lifetime Achievement Award for its outstanding contributions to recorded classical music.

The quartet plays a wide range of classical music, and has recorded works by composers such as Beethoven, Mendelssohn, Bartók, Debussy, and Shostakovich, while also promoting more contemporary composers such as Elliott Carter, Ralph Shapey, Henri Dutilleux and Milton Babbitt. It has performed with other noted musicians such as Aaron Copland, Glenn Gould, Benita Valente and also (in its earlier days) with the famous scientist Albert Einstein.