Adagio and Fugue in C minor, K. 546, is a composition by Wolfgang Amadeus Mozart, dated "Vienna, 26 June 1788". The Fugue is a transcription of his Fugue in C minor for two pianos, K. 426, which he wrote in 1783. The adagio, which was not part of K. 426, is written in the time signature of 3/4 time, the fugue in alla breve and its tempo designation is allegro. The work is scored for first and second violins, viola, and cello plus double bass.
It is partly inspired by the contrapuntal style of Johann Sebastian Bach. The Bach background of the piece can be heard with the underlying dark intensity along with a gradual style change from the classicism of Mozart’s time to a more Baroque style. Also, the fugue style of the piece reflects Bach's influence on Mozart. Mozart was introduced to the music of Bach and Handel in 1782 by his patron Gottfried van Swieten.