Blainville was born at Arques, near Dieppe. As a young man he went to Paris to study art, but ultimately devoted himself to natural history. He attracted the attention of Georges Cuvier, for whom he occasionally substituted as lecturer at the Collège de France and at the Athenaeum Club, London. In 1812 he was aided by Cuvier in acquiring the position of assistant professor of anatomy and zoology in the Faculty of Sciences at Paris. Eventually, relations between the two men soured, a situation that 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, of which he proved himself a worthy successor to his former teacher.
In 1837, he was elected a foreign member of the Royal Swedish Academy of Sciences. On May 1, 1850, he died from an attack of apoplexy in a railway carriage at the Embarcadère du Havre (current Gare Saint-Lazare) in Paris.
He was the taxonomic authority of numerous zoological species, extinct and extant; including the eponymous Blainville's beaked whale, Mesoplodon densirostris.
In the field of herpetology, he adopted Pierre André Latreille's proposal of separating Amphibia from Reptilia, and then (1816) developed a unique arrangement in regards to sub-groupings, using organs of generation as primary criteria. He described several new species of reptiles.
Blainville rejected evolution. He was a critic of Lamarck's evolutionary ideas but similar to Lamarck proposed a great chain of being.
It was in 1822 that he coined the term paleontology.