String Quartet in B-flat major

String Quartet in B-flat major may refer to:
 * No. 4 of the String Quartets, Op. 33 (Haydn)
 * No. 1 of the String Quartets, Op. 50 (Haydn)
 * No. 3 of the String Quartets, Op. 64 (Haydn)
 * No. 4 of the String Quartets, Op. 76 (Haydn)
 * String Quartet No. 6 (Mozart)
 * String Quartet No. 12 (Mozart)
 * String Quartet No. 17 (Mozart)
 * String Quartet No. 22 (Mozart)
 * String Quartet No. 6 (Beethoven)
 * String Quartet No. 13 (Beethoven)
 * String Quartet No. 3 (Schubert)
 * String Quartet No. 5 (Schubert)
 * String Quartet No. 8 (Schubert)
 * String Quartet No. 3 (Brahms)
 * Quartet Movement in B-flat major (Tchaikovsky)
 * String Quartet No. 2 (Dvořák)
 * String Quartet in B-flat major (Sibelius)
 * String Quartet No. 1 (Hill)
 * String Quartet No. 5 (Shostakovich)