Friedrich Wilhelm "Fritz" Strassmann (1902 – 1980) was a German chemist.
In 1934, Strassmann joined Otto Hahn and Lise Meitner in their investigation of the bombardment of uranium with neutrons. His expertise in chemistry contributed to the recognition of the lighter elements produced from neutron bombardment, most notably barium. This would lead to the discovery of nuclear "fission" and the revelation that such a process could be used to create a weapon of mass destruction.
During the War, Strassmann was on the Alsos list, the Manhattan Project's military intelligence effort to capture known, enemy nuclear scientists in an attempt to learn how far Germany had progressed in its efforts to develop a nuclear weapon. It was soon revealed, however, that Strassmann was not involved in any German attempt to build an atomic bomb. In fact, he and his wife Maria had concealed a Jewish friend in their apartment for months during the war, putting themselves and their three year old son at risk.