Of Chinese/Australian heritage, Tessa Kum was raised in Melbourne and has an honors degree in creative writing. She is also a graduate of the Clarion South Writers Workshop. Although she has had a passion for writing since early childhood Kum nevertheless describes herself as a part-time writer, not yet having written a novel and publishing short fiction only sporadically. Since her first work was accepted for publication at age twenty she has been published in anthologies such as Machinations (2002), Elsewhere (2003), Daikaiju 3 (2007), Last Drink Bird Head (2009), Halo: Evolutions (2009, with Jeff VanderMeer), and The Year's Best Australian Fantasy and Horror (2010). Kum has also been published in Andromedia Spaceways Inflight Magazine and has served as an editorial assistant for Weird Tales (2008-2011) and assistant editor for the Best American Fantasy series.
From around 2006 Kum was employed in a data entry position while writing in her spare time, a combination which led to her developing a Repetitive Strain Injury (RSI) after some three years. She began offering her services as a freelance editor and manuscript assessor in 2008, and has continued to work in this field since then. One of her more recent assignments was as assistant editor for forthcoming Time Traveller's Almanac (2014). After living briefly in Glasgow in 2012 Kum returned to live in Melbourne in early 2013.