Leo Löwenthal (3 November 1900 – 21 January 1993) was a German sociologist usually associated with the Frankfurt School.
Born in Frankfurt as the son of assimilated Jews (his father was a physician), Löwenthal came of age during the turbulent early years of the Weimar Republic. He joined the newly founded Institute for Social Research in 1926 and quickly became its leading expert on the sociology of literature and mass culture as well as the managing editor of the journal it launched in 1932, the Zeitschrift für Sozialforschung. Heterodox and independent Marxists, open to new intellectual currents such as psychoanalysis, and predominantly Jewish, the Institute's members swiftly fled Germany when Adolf Hitler came to power in 1933. After a year in Geneva, they settled in New York, where Columbia University gave them shelter.
Löwenthal maintained a close relationship with his colleagues, even during the war when several of them moved to California and he began to work with the Office of War Information in Washington. Although Horkheimer, Adorno, and Friedrich Pollock returned to Frankfurt to reestablish the Institute after the war, Löwenthal, like former members Herbert Marcuse, Franz Neumann, Otto Kirchheimer, and Erich Fromm, chose to remain in the United States. After seven years as research director of the Voice of America, and another year at the Stanford Center for the Advanced Study of the Behavioral Sciences, he joined the Berkeley Speech Department in 1956 and shortly thereafter the Department of Sociology. Although officially retiring in 1968, Löwenthal remained vigorously active in departmental and University affairs until virtually the end of his life. From 1968 to 1972, he served on the Budget Committee, and in 1973-74, chaired the Sociology Department.