The Symphony No. 2 in D minor, opus 40, by Sergei Prokofiev was written from 1924 to 1925.

The piece is in just two movements, the first marked "Allegro ben articolato" and the second a theme and six variations. This overall structure of a quick, minor-key first movement followed by a set of variations which begins more calmly, was fashioned after Ludwig van Beethoven's Piano Sonata No. 32, his last. In other respects, however, the piece is decidedly twentieth century. The first movement in particular is rhythmically unrelenting, and the harmonies are highly dissonant.

The piece was premiered in Paris on June 6, 1925, conducted by Serge Koussevitzky, and was not well received; Prokofiev commented that neither the audience or himself understood the piece. It has remained a somewhat obscure work, possibly the least-played of Prokofiev's seven symphonies.

Prokofiev planned to revise the piece late in his life, going so far as to assign the project the opus number 136, but this plan never came to fruition.