He is not to be confused with the dipterist Richard Karl Hjalmar Frey or with the early Pennsylvania pioneer, Heinrich Frey, who is considered one of the first two German immigrants to the American Colonies see Fry family.
Heinrich Frey attended the gymnasium in Frankfurt am Main until he was 16. Here he met Senator Carl Heinrich Georg von Heyden (1793–1866) who introduced him to entomology. He attended the University in Frankfurt am Main, then travelled to Bonn, Berlin, and Göttingen.
When he returned to Frankfurt am Main in 1839 von Heyden showed him Philipp Christoph Zeller's Attempt at a Classification of the Tineinae which had just appeared in Oken's Isis. Until this publication, this group of moths had been hopelessly confused and Frey was impressed by Zeller's orderly arrangement.
Returning to Göttingen in 1847 he first became a private tutor, then an “extraordinary” professor at the University. (An extraordinary professorial chair is one created by a university because of an application from an outside organisation that feels that a certain field is not given enough attention). In 1849, he was offered a professorial post by the University of Zurich, which he accepted.
In 1851, Frey became an ordinary professor in the Medical Faculty, soon after also becoming a Professor at the confederate Polytechnikum. He also became Director of the microscopical anatomical institute and from 1854 to 1856 Rector of the High School. Frey spent the rest of his life in Switzerland.
His most important publications were:
- Heinrich Frey, Der Lepidopteren der Schweiz, W. Engelmann, 1880 Electronic text Der Lepidopteren der Schweiz
- With Henry Tibbats Stainton, Philipp Christoph Zeller and John Douglas parts of The Natural History of the Tineina 13 volumes, 2000 pages 1855 Volumes 2 -13 online here
- Heinrich Frey, Die Tineen und Pterophoren der Schweiz: i-xii, 1-430. Zurich. Gronlien (1856)
- Gaedike, R.; Groll, E. K. & Taeger, A. 2012: Bibliography of the entomological literature from the beginning until 1863 : online database - version 1.0 - Senckenberg Deutsches Entomologisches Institut.