Johann Joachim Quantz (January 30, 1697–July 12, 1773) was a German flutist, flute maker and composer. He was born in Oberscheden , near Göttingen, Germany, and died in Potsdam.

Quantz began his musical studies as a child with his uncle (his blacksmith father died when Quantz was young), later going to Dresden and Vienna. It was during his time as musician to Frederick Augustus II of Poland that he began to concentrate on the flute, performing more and more on the instrument. He gradually became known as the finest flautist in Europe, and toured France and England. He became flute teacher, flute maker and composer to Frederick II of Prussia (Frederick the Great) in 1740. He was an innovator in flute design, adding keys to the instrument to help with intonation (playing in tune), for example.

Although Quantz wrote many pieces of music, mainly for the flute (including around 300 flute concertos), he is best known today as the author of Versuch einer Anweisung die Flöte traversière zu spielen (1752), a treatise on flute playing. It is of great interest today as a source of information on performance practice and flute technique in the 18th century.