1766 in music
- November 29 – Wolfgang Amadeus Mozart returns to Salzburg after the Mozart family grand tour of Europe.
- Joseph Haydn becomes Kapellmeister to the house of Esterházy and their orchestra is increased to 22 players.
- Niccolò Piccinni is invited to Paris by Queen Marie Antoinette.
- Dom Bédos de Celles publishes his influential L'art du facteur d'orgues.
- New Drottningholm Palace Theatre in Stockholm is completed as an opera house.
- Egidio Romualdo Duni – La clochette
- Joseph Haydn – La Canterina (libretto by an unknown, based on material by Carlo Goldoni)
- Johann Adam Hiller – Der lustige Schuster
- Carl Philipp Emmanuel Bach – Pieces (40) for Keyboard, Wq 117: no. 2, Solfeggio in C minor, H 220
- Capel Bond – Six Concertos in Seven Parts
- Joseph Haydn – Great Mass in E flat
- Michael Haydn – Symphony in B-flat major
- Niccolò Jommelli – Missa Solemne
- February 24 – Samuel Wesley, organist and composer (died 1837)
- March 28 – Joseph Weigl, composer and conductor (died 1846)
- July 19 – Johann Anton Friedrich Fleischmann, composer (died 1798)
- July 21 – Carolina, Baroness Nairne, Scottish songwriter (died 1845)
- August 1 – Ignace Antoine Ladurner, pianist and composer (died 1839)
- August 22 – Joseph-Denis Doche, composer (died 1825)
- October 9 – Bedřich Diviš Weber, composer and founding principal of the Prague Conservatory (died 1842)
- November 16 – Rodolphe Kreutzer, violinist and composer (died 1831)
- November 20 – John Wall Callcott, composer (died 1821)
- January 30 – Susannah Maria Arne, singer (born 1714)
- February 26 – August Bernhard Valentin Herbing, composer (born 1735)
- March 3 – Gregor Werner, composer and leader of Prince Paul Esterházy's orchestra (born 1693)
- March 20 – Giovanni Battista Pescetti, organist and composer (born c. 1704)
- March 25 – Johannes Ritschel, composer (born 1739)
- April – François Étienne Blanchet II, harpsichord maker (born 1730)
- October 7 – André Chéron, composer (born 1695)
- November 9 – Unico Wilhelm van Wassenaer, composer (born 1692)
- December – Carlo Tessarini, violinist and composer (born c. 1690)
- date unknown – Alvise Giusti, librettist (born 1709)