Franz Firbas (* June 4, 1902 in Prague; † February 19, 1964 in Göttingen) was a German botanist who taught at the University of Gottingen. From 1952-1964, he was director of their Systematisch-Geobotanisches Institut. Former students include Gerhard Lang and Heinz Ellenberg.
Firbas studied at the German branch of Charles University (German Charles-Ferdinand University) under Prof. K. Rudolph. He was an assistant professor for a short time, before leaving to go to Germany.