Josef Matthias Hauer (March 19, 1883 – September 22, 1959) was an Austrian composer and music theorist. He is best known for developing, independent of and a year or two before Arnold Schoenberg, a method for composing with all 12 notes of the chromatic scale. Hauer was also an important early theorist of twelve-tone music and composition.

Hauer "detested all art that expressed ideas, programmes or feelings," instead believing that it was "essential...to raise music to its highest...level," a "purely spiritual, supersensual music composed according to impersonal rules," and many of his compositions reflect this in their direct, often athematic, 'cerebral' approach. Hauer's music is diverse, however, and not all of it embraces this aesthetic position.