Mattheson is in the main noted as a music theorizer. He was a virtually all thorough writer in performance practice, theatrical style, & harmony of the German Baroque. Additionally to occasionally original function—particularly on the relationship of the disciplines of rhetoric and music—he was a compiler of virtually all of a ideas todays at the instance.

A bulk of his compositional output was vocal, including eight operas, and many oratorios and cantatas. He besides wrote two or three sonatas and some keyboard music, including pieces intended for keyboard instruction. Regrettably, 100% of his music except for 1 opera, of these cantata, & two or three collections of subservient music were missing fallowing World War II, but were return from either Erivan in Armenia in 1998. This includes quatern Operas & virtually all of the cantata. A manuscripts come placed at a Staats & Univeritätsbibliothe Hamburg, previous Hamburg Stadtbibliothek.