Moriarty was raised in the north-west suburbs of Sydney. She has four sisters and one brother. Two of her sisters, Liane and Nicola, are also novelists. Moriarty studied English and Law at the University of Sydney upon graduating from high school. She then complete a Masters in Law at Yale University and a PhD at Gonville and Caius College, Cambridge^[1]

She worked as an entertainment and media lawyer for four years before becoming a full-time writer. The literary agent who picked up her first book, Feeling Sorry for Celia, was Australian author Garth Nix.^[1] Moriarty was previously married to Canadian writer Colin McAdam, and they have one young son, Charlie. She currently lives in Sydney.

The Ashbury/Brookfield Series is four novels that are not sequels but are linked. They all revolve around various students that attend the exclusive private school, Ashbury High, or the local comprehensive, Brookfield High. Many of the students cross over into more than one novel, but each novel is different and tells a different story. All novels are told through the various character's own writing (through letters, emails, exam papers, etc.).^[2]

The Ashbury/Brookfield series of novels are (in chronological order):

• Feeling Sorry for Celia (2000)
• Finding Cassie Crazy (2003) (AUS/UK title) The Year of Secret Assignments (US title)
• The Betrayal of Bindy Mackenzie (2006) (AUS title) also published as Becoming Bindy Mackenzie (UK title), and The Murder of Bindy Mackenzie (US title)
• Dreaming of Amelia (2009) (AUS/UK title) also published as The Ghosts of Ashbury High (US title)

This trilogy retains some familiar features of Moriarty's style, such as a loosely epistolary form (the use of alternating chapters in which characters speak in their own quite distinctive voices); a sneaky sense of humor; and a plot that keeps the reader off balance by constantly subverting the 'facts' that one thought one understood. But it also marks a departure in the direction of fantasy: the premise of the trilogy is, or at least appears to be, the existence of an almost fairyland-like parallel world, sealed off from our world but in connection with it via 'cracks,' through which letters, or even people, can travel. As usual with Moriarty, nothing is quite what it seems, and incidents and ideas that appeared incidental may turn out to be central. All three of the books in the trilogy have been released.

• A Corner of White, Sydney Pan Macmillan (published 2012), 2013, ISBN 978-1-74261-139-6
• The Cracks in the Kingdom, Sydney, New South Wales Pan Australia, 2014, ISBN 978-1-74261-287-4. Winner: Ethel Turner Prize for Young People's Literature, New South Wales Premier's Literary Awards 2015.^[3]
• A Tangle of Gold, Sydney Pan, 2016, ISBN 978-1-74353-323-9

• The Extremely Inconvenient Adventures of Bronte Mettlestone (2017)
• The Slightly Alarming Tale of the Whispering Wars (2018) ISBN 9781760297183 – winner of the 2019 Griffith University Children's Book Award at the Queensland Literary Awards^[4]
• The Stolen Prince of Cloudburst (2020) ISBN 9781760875060 – shortlisted for 2021 Children's Book of the Year Award: Younger Readers^[5] and for the 2021 Children's Book Award at the Queensland Literary Awards^[6]
• The Astonishing Chronicles of Oscar from Elsewhere (2021) ISBN 9781760526368
• The Impossible Secret of Lillian Velvet (2023) – shortlisted for the 2024 Children's Indie Book Award^[7]

• I Have a Bed Made of Buttermilk Pancakes (2004)
• The Spell Book of Listen Taylor (2007) a young adult novel that is an adaptation of I Have a Bed Made of Buttermilk Pancakes.
• Gravity is the Thing (2019) ISBN 9781760559502

• Jaclyn Moriarty's Official Website
• Jaclyn Moriarty's Blog