Leopoldo Maggi (Rancio Valcuvia, near Varese, May 15, 1840 – Pavia, March 7, 1905) was an Italian physician, craniologist and naturalist.

In 1863 he obtained two degrees: in Natural sciences and in Medicine and surgery and became assistant first to Paolo Panceri (1833-1877) the teacher of several other outstanding Italian zoologists of the end of the 19th century and then to Giuseppe Balsamo Crivelli.

When zoology became a separate subject in 1875 he held the chair of Comparatve anatomy and Physiology occupying this until his death.

[2] For years he devoted himself to biology and especially to comparative anatomy, but also to Mineralogy, Osteology, Prehistoric archaeology, craniology and Protistology.

[3] The studies of Leopoldo Maggi, at first eminently descriptive with the discovery of numerous taxa, had a rapid evolution in the medical field and converged in bacteriology.