Karl Walter Schröter (7 September 1905 in Biebrich near Wiesbaden – 22 August 1977 in Berlin) was a German mathematician and logician.
Later on, after the war, he made important contributions concerning semantic consequences (German: semantische Folgerungsrelationen) and provability logic (German: syntaktische Ableitbarkeitsrelationen).
He worked as a mathematical theoretician and cryptanalyst for the civilian Pers Z S, the cipher bureau of the Foreign Office (German: Auswärtiges Amt), from Spring 1941 to the end of World War II.