Jaroslav Krejčí (27 June 1892, Konice, Margraviate of Moravia – 18 May 1956) was a Czech lawyer and Nazi collaborator. He served as the prime minister of the Protectorate of Bohemia and Moravia from 28 September 1941 to 19 January 1945. After graduating from the Faculty of Law of Charles University in 1915 he worked in the civil service in various positions. During the 1930s he also lectured on constitutional law at Masaryk University (from 1938 as professor). Wolf Gruner wrote that Krejčí "enthusiastically paid homage to Nazi rule".