Pietro Rossi (23 January 1738 in Florence – 21 December 1804 in Pisa) was an Italian scientist and entomologist.
Rossi's academic career was conducted at the University of Pisa, where he attained a doctorate in philosophy and medicine in 1759.
His publications, particularly Fauna etrusca (1790) and Mantissa insectorum (1792), are considered pioneer achievements of entomology and still possess scientific validity in the fields of taxonomy and biological nomenclature.
Parts of his collection were once in the possession of Johann Christian Ludwig Hellwig in Braunschweig; these are now in the Natural History Museum of Berlin.
In 1793, he was elected a foreign member of the Royal Swedish Academy of Sciences.