Otto Heinrich Greve (30 January 1908 in Rostock, Mecklenburg-Schwerin, Germany – 11 June 1968 in Ascona, Ticino, Switzerland) was a German lawyer by profession and a politician of the German Democratic Party (DDP) and its successor German State Party (DStP; 1926 to 1933, when the Nazis banned that party), the Free Democratic Party (F.D.P.; 1945 to 1947) and Social Democratic Party of Germany (SPD; since 1948) and a member of the German Bundestag.