Carl Friedrich Roewer (12 October 1881, Neustrelitz – 17 June 1963) was a German arachnologist. He concentrated on harvestmen, where he described almost a third (2,260) of today's known species, but also almost 700 taxa of spiders and numerous Solifugae. He joined the Nazi Party in the 1930's. From 1933 on, he was the second director of the Übersee-Museum in Bremen, Germany. Under his direction the museum intensified its advocacy of scientific racism.