Anti-Defamation League (ADL) er en amerikansk, jødisk lobbyorganisation grundlagt i 1913 med det formål at stoppe krænkelse af jøder og jødedom. ADL's formålsparagraf slår fast at "[t]he immediate object of the League is to stop, by appeals to reason and conscience and, if necessary, by appeals to law, the defamation of the Jewish people. Its ultimate purpose is to secure justice and fair treatment to all citizens alikeand to put an end forever to unjust and unfair discrimination against and ridicule of any sect or body of citizens".