1546 in science
- Hieronymus Bock publishes the second, illustrated, edition of his flora of Germany, the Kreutterbuch.
- Antonio Musa Brassavola of Ferrara publishes the first definitely recorded successful tracheostomy.
- Valerius Cordus' pharmacopoeia Dispensatorium published posthumously in Nuremberg.
- Girolamo Fracastoro, in his De Contagione et Contagiosis Morbis (published in Venice), discusses the transmission of infectious diseases and gives the first description of typhus.
- Giovanni Filippo Ingrassia describes the stapes bone of the middle ear.
- December 14 – Tycho Brahe, Danish astronomer (died 1601).
- date unknown
- approx. date – Paul Wittich, German astronomer and mathematician (died 1586)
- Goodall, E. W. (1934). "The story of tracheostomy". British Journal of Children's Diseases. 31: 167–76, 253–72.