Jean Pierre Mégnin (18 January 1828 – 30 December 1905) was a French army veterinarian and entomologist.
He is best known for his work with dogs and forensic entomology.
Mégnin, born in Herimoncourt (Doubs), went to school at the Ecole d'Alfort from 1849 until his graduation in 1853.
In 1855, he became an army veterinarian and was, sometime, Professor of Zoology at the School of Veterinary Medicine in Vincennes.
His life spanned three periods of the history of France.