Florian Johann Deller was an Austrian composer and violinist.
In 1751 he was a violinist at the court orchestra in Stuttgart. There he studied with Niccolo Jommelli. Later he became assistant to the ballet master Jean Georges Noverre and composed operas and ballets. In 1769 he was appointed Concertmaster and Hofcompositeur. In 1771 he moved to Vienna. Deller died in 1773 in the monastery of the Brothers of Mercy in Munich.
His compositional output consists mostly of operas, ballet music, sonatas and minuets. He enjoyed in his lifetime a high reputation as a composer. His works have been greatly appreciated, by, among others Mozart and Christian Friedrich Daniel Schubart. Many of his works are considered lost.