Hans Fruhstorfer (7 March 1866 Passau, Germany – 9 April 1922 Munich) was a German explorer, insect trader and entomologist who specialised in Lepidoptera. He collected and described new species of exotic butterflies, especially in Adalbert Seitz's Macrolepidoptera of the World. He is best known for his work on the butterflies of Java. Fruhstorfer's collections are deposited at the Museum für Naturkunde in Berlin, the Natural History Museum in London and the Muséum national d'histoire naturelle in Paris, as well as in many other museums.