Otto Carl Reche (24 May 1879 – 23 March 1966) was a German anthropologist and professor from Glatz (Kłodzko), Prussian Silesia. He was active in researching whether there was a correlation between blood types and race. During the Second World War he openly advocated the genocide of ethnic Poles. Once a member of the Nazi Party, he remained active in anthropological issues following the downfall of Nazi Germany.