The String Quartet No. 2 by Béla Bartók was written between 1915 and October 1917 in Rákoskeresztúr in Hungary.

The work is in three movements:

  1. Moderato
  2. Allegro molto capriccioso
  3. Lento

In a letter to André Gertier, Bartók described the first movement as being in sonata form, the second as "a kind of rondo" and the third as "difficult to define" but possibly a sort of ternary form.

The work is dedicated to the Waldbauer-Kerpely Quartet, and it was they who gave the piece its premiere on March 3, 1918 in Budapest. The work was first published in 1920 by Universal Edition.