Austrian musician who composed more than 100 stage works and much instrumental and church music that was extremely popular in his own time, although it is almost entirely absent from the modern repertoire.

Seyfried, who knew Mozart, studied with Johann Georg Albrechtsberger (one of Beethoven's teachers), among others. He was a highly successful conductor-producer (1797–1828) of operas in Vienna and was also a music theorist of considerable reputation. He edited a collection of Albrechtsberger's works on harmony (1826) and studies in technique and composition by Beethoven (1832).