At the age of eighteen, Bray was involved in a serious car accident and had to undergo thirteen surgeries in six years to reconstruct her face. She has an artificial left eye because of this accident.

Bray graduated from the University of Texas at Austin in 1988 as a Theatre major. As a budding playwright, she felt it important to be in New York. When her childhood best friend, already living in Manhattan, called saying she was looking for a roommate, Bray was soon on her way to New York. Her first job was in the publicity department of Penguin Putnam, followed by three years at Spier, an advertising agency specializing in book advertising.

Bray was encouraged to write a young adult novel by her husband, Barry Goldblatt, a children's book agent and Ginee Seo, an editor at Simon & Schuster. Before this, using a pseudonym, she had written three books for 17th Street Press (a publisher of romances).

Her first novel, A Great and Terrible Beauty became a New York Times bestseller. In November 2006, a video promoting the book was a part of The Book Standard's Teen Book Video Awards. She wrote two more books to finish the trilogy she had started with A Great and Terrible Beauty: Rebel Angels and The Sweet Far Thing.

Libba is friends with many young adult authors including Maureen Johnson. Bray is also good friends with fellow YA fantasy authors Holly Black and Cassandra Clare; all of them are represented by Bray's husband, a literary agent. Her blog can be read on http://libba-bray.livejournal.com/.

Bray has recently published a new novel titled Going Bovine which is a dark comedy about a 16 year old boy named Cameron who has mad cow disease and a 16-year-old dwarf named Gonzo whom he met in the hospital. Gonzo is a video gamer who thinks that everything is trying to kill him. Cameron has visitation from a punkish angel named Dulcie who has a propensity for spray-painting her wings. They are all on a mission to cure Cameron's mad cow disease. Going Bovine was released in 2009 and received the 2010 Michael L. Printz Award for excellence in young adult literature.