Jeph Loeb was born in Stamford, Connecticut. He reportedly read his first comic book during the summer of 1970. By winter of the same year, Jeph was apparently fascinated enough to convince his father to purchase the comic book collection of one "Tom Chicarella" on his behalf. Tom was from Brooklyn, New York and the sold collection reportedly included every issue published by Marvel Comics between 1961 and late 1970.
His later stepfather was a vice-president at Brandeis University in Waltham, Massachusetts, where Jeph met one of his mentors and greatest influences in comic book writing, writer Elliot Maggin. Jeph however attended Columbia University. He graduated with a Bachelor of Arts and a Master's degree in Film.
- Tim Sale (his frequent partner)