Fritz Walther Meißner (or Meissner) (December 16, 1882, Berlin - November 16, 1974, Munich) was a German technical physicist.
He studied mechanical engineering and physics at Munich Institute of Technology, his doctoral supervisor being Max Planck. He then entered the Physikalisch-Technische Reichsanstalt. From 1922 to 1925, he established the world's third largest Helium-liquifier, and discovered in 1933 the Meissner effect, damping of the magnetic field in superconductors. One year later, he was called as chair in technical physics at the Institute of Technology in Munich. After World War II, he became the president of the Bavarian Academy of Sciences and Humanities. In 1946, he was appointed director of the academy's first low temperature research commission. Laboratories were located in Herrsching am Ammersee until 1965, when they were moved to Garching. Walther Meißner died in Munich in 1974.