String Quartet No. 15 may refer to:
String Quartet No. 15 (Beethoven) by Ludwig van Beethoven String Quartet No. 15 (Hill) by Alfred Hill String Quartet No. 15 (Milhaud), Op. 291, No. 2, by Darius Milhaud String Quartet No. 15 (Mozart) by Wolfgang Amadeus Mozart String Quartet No. 15 (Schubert) by Franz Schubert String Quartet No. 15 (Shostakovich) by Dmitri Shostakovich String Quartet No. 15 (Simpson) by Robert Simpson String Quartet No. 15 (Spohr) by Louis Spohr String Quartet No. 15 (Villa-Lobos) by Heitor Villa-Lobos