She was born in the borough of Brooklyn.
Mindy graduated from the Beth Israel Medical Center School of Nursing, attended Quinnipiac College for biology, and worked as a nurse. She has a daughter named Alixandra, whose name would be used in her "Jenesis" series in New Talent Showcase.
Mindy Newell sent submissions in to DC Comics at a time when they were actively trying to recruit new talent, and one of them (Jenesis) was immediately commissioned for the New Talent Showcase title. She subsequently wrote issues of Legion of Super-Heroes, Action Comics, Wonder Woman, Amethyst, Catwoman and a Lois Lane limited series as well as American Flagg for First Comics and New Wave for Eclipse before moving on to an editorial position at Marvel Comics in 1990. She has since returned to nursing.