Henri Marie Ducrotay de Blainville (September 12, 1777 - May 1, 1850) was a French zoologist and anatomist.

Blainville was born at Arques, near Dieppe. In about 1796 he went to Paris to study painting, but he ultimately devoted himself to natural history, and attracted the attention of Georges Cuvier, for whom he occasionally lectured at the College de France and at the Athenaeum. In 1812 he was aided by Cuvier to obtain the chair of anatomy and zoology in the Faculty of Sciences at Paris, but subsequently an estrangement grew up between the two men and ended in open enmity.

In 1825 Blainville was admitted a member of the French Academy of Sciences; and in 1830 he was appointed to succeed Jean-Baptiste Lamarck in the chair of natural history at the museum. Two years later, on the death of Cuvier, he obtained the chair of comparative anatomy, which he continued to occupy for the space of eighteen years, proving himself no unworthy successor to his great teacher. He was found dead in a railway carriage while travelling between Rouen and Caen.

Besides many separate memoirs, he was the author of Prodrome d'une nouvelle distribution du règne animal (1816); Ostéographie ou description iconographique comparée du squelette et du système dentaire des mammifères récents et fossiles (1839-1864); Faune francaise (1821-1830); Cours de physiologie generale et comparee (1833); Manuel de malacologie et de conchyliologie (1825-1827); Histoire des sciences de l'organisme (1845).