The Symphony No. 1 in E-flat major, KV. 16, was written in 1764 by Wolfgang Amadeus Mozart at the age of just eight years. By this time, he was already notable in Europe as a wunderkind performer, but had composed little music.

The symphony is written for an orchestra  consisting of two oboes, two horns and strings (the usual first and second violins, violas, cellos and double basses). It is laid out in a three-movement, quick-slow-quick form, reflecting the genre's origins in the Italian overture, and typical of the early classical symphony:

   1. Molto allegro, 4/4
   2. Andante, 2/4 in C minor
   3. Presto, 3/8

The first movement of the symphony is a quick piece in bipartite sonata form. The first half of the movement serves as the exposition with two theme groups in the tonic and dominant. In the second half, the first theme group is developed in the dominant and submediant keys while the second theme group is recapitulated in the tonic.

The second is slower, in the relative key of C minor, with an almost constant accompaniment of semiquaver (sixteenth note) triplets. The movement focuses on tone color rather than any melodic ideas.

The third is fast and lively, making great play of contrasts between quiet and loud passages, and parts played only by the violins and parts played by the entire orchestra.