Wilhelm Walcher (7 July 1910 in Kaufbeuren – 9 November 2005 in Marburg) was a German experimental physicist. During World War II, he worked on the German nuclear energy project, also known as the Uranium Club; he worked on mass spectrometers for isotope separation. After the war, he was director of the Institute of Physics at the University of Marburg. He was a president of the German Physical Society and a vice president of the German Research Foundation. He helped found the Society for Heavy Ion Research and the German Electron Synchrotron DESY. He was also one of the 18 signatories of the Göttingen Manifest.