Johann Christian Fischer (c. 1733 – 29 April 1800) was a German composer and oboist, one of the best-known oboe soloists in Europe during the 1770s.
Employed as a music copyist and theatre director for the Duke of Mecklenburg-Schwerin at Ludwigslust, Fischer is now credited with the unique Symphony with Eight Obbligato Timpani, formerly attributed to Johann Wilhelm Hertel, court composer at Schwerin. He spent some time in Dresden, but left after the Prussian occupation in the Seven Years' War for extensive concertizing tours, ending in London, where he was active as a performer, composer, and a teacher, and introduced the Continental narrow-bore model of oboe that replaced the bright and penetrating straight-topped English type In London Fischer joined the largely German "Queen's Band" of George III's German Queen, Charlotte of Mecklenburg-Strelitz. Fischer published several teaching manuals for the oboe, with varying titles: The Compleat Tutor for the Hautboy (ca 1770), New and Complete Instructions for the Oboe or Hoboy (ca 1780) and The Hoboy Preceptor (1800). Among his students was composer and oboist Charles J. Suck.
An etching/aquatint A Sunday concert by Charles Loraine Smith, published 4 June 1782, shows a distinguished musical group gathered round a harpsichord, with Fischer and Charles Burney among them.
Mozart composed a set of Twelve Variations in C on a Menuett of Johann Christian Fischer (K.179 [189a]).