Gustav von Hayek (21 March 1836 in Brno – 11 January 1911 in Vienna) was an Austrian naturalist.
He was the father of botanist August von Hayek (1871–1928) and the grandfather of economist Friedrich von Hayek (1899–1992).
He studied natural sciences at the University of Vienna, and served as an assistant to naturalist Andreas Kornhuber (1824–1905).
Following graduation in 1869, he worked as a Gymnasialprofessor of natural sciences and chemistry in Vienna (1869 to 1901).
He was also author of the four volume "Handbuch der Zoologie", published from 1877 to 1893:
Volume I: Protozoa, Coelenterata, Echinodermata und Vermes, 1877
Volume II: Arthropoda, 1881
Volume III: Mollusca, Vertebrata Anallantoidica, 1885
Volume IV: Vertebrata Allantoidica: Reptilia, Aves, Mammalia, 1893.