Martin Julius Hertz (7 April 1818, in Hamburg – 22 September 1895) was a German classical philologist, a student and biographer of Karl Lachmann.
He studied philology at the Universities of Bonn and Berlin, where his instructors included August Boeckh (1785–1867) and Karl Lachmann (1793–1851), the latter being an important influence to Hertz' career.
He earned his doctorate in 1842, followed by his habilitation a few years later (1845).
Afterwards, he embarked on an educational journey throughout Europe (southern Germany, Netherlands, Belgium, France, Italy and Austria).
He is especially known for his critical editions of Priscian and Aulus Gellius.