Antonín Dvořák's String Quintet No. 2 in G major, Op. 77 (B. 49), was originally composed in early March 1875 and first performed on 18 March 1876 in Prague at the concert of the Umělecká beseda. The string quintet is scored for two violins, viola, cello, and double bass.

First marked as Op. 18, it was later slightly revised in 1888 and printed with the misleading opus number 77 by the publisher Simrock. It has since been assigned the Burghauser number B. 49. Dvořák entered the piece in a competition and was awarded 5 ducats for the composition. The work bears the competition's motto, "To my Nation", as its dedication. The quintet marks an advance in comparison with Dvořák's early works for chamber ensemble, as it is not only technically more refined with a more balanced structure, but with the addition of a double bass as the fifth instrument has a more imposing sound while permitting the cello to move up to a higher, more lyrical position within the group.

Although the original work was scored in five movements, Dvořák later withdrew the second movement, entitled "Intermezzo," due to concerns that having two slow movements made the work too lengthy. This extracted movement had been based on the central section, marked 'Andante religioso', of his String Quartet No. 4 (which was not published in his lifetime), and was in turn later reworked and republished as the Nocturne for Strings in B major, Op. 40 (B. 47). Some modern ensembles choose to restore the intermezzo when performing the work.