Alfred Einstein (December 30, 1880 – February 13, 1952) was a German-American musicologist and music editor. He is best known for being the editor of the first major revision of the Köchel catalogue, which was published in the year 1936. The Köchel catalogue is the extensive catalogue of the works of Wolfgang Amadeus Mozart. Einstein was known to have had such a depth of familiarity with Mozart that he had something pertinent to say about every piece Mozart wrote.