|Occupation||Science fiction author|
|Genre||Military science fiction|
Kloos is best known for his Frontlines series of military science fiction novels. Featuring the protagonist Andrew Grayson, they are set in a future in which a Western and an Eastern power bloc are at war with each other and with an alien threat.
Reviewing the first novel, Terms of Enlistment, io9 described it as sticking close to the conventions of the genre, focusing on "guns, acronyms, hard-ass drill sergeants, explosions and battles on alien worlds". The reviewer considered the second novel, Lines of Departure, to be an improvement in that it reflected a critical outlook towards powerful, centralized government that was often absent in leading works of the genre such as Robert Heinlein's Starship Troopers.
Lines of Departure was nominated for the 2015 Hugo Award for Best Novel on a slate organized by the "Sad Puppies", a group of "right-leaning science fiction writers." In reaction to this, Kloos withdrew the novel from consideration for the award. He was subsequently honored by George R. R. Martin for this decision.
In 2019, his short story, Lucky Thirteen, was adapted as part of the Netflix anthology series Love, Death & Robots.
Aftershocks, the first book in a new series, "The Palladium Wars," was released in July 2019.
Kloos lives in New Hampshire with his family and has been employed as "a soldier, a bookseller, a freight dock worker, a tech support drone, and a corporate IT administrator". He is a graduate of the Viable Paradise writers' workshop.
- Terms of Enlistment (2013), ISBN 978-1-4778-0978-5, 47North
- Lines of Departure (2014), ISBN 978-1-4778-1740-7, 47North
- Angles of Attack (2015), ISBN 978-1-4778-2831-1, 47North
- Chains of Command (2016), ISBN 978-1-5039-5032-0, 47North
- Fields of Fire (2017), ISBN 978-1-5039-4071-0, 47North
- Points of Impact (2018), ISBN 978-1-5420-4846-0, 47North
- Lucky Thirteen (2013)
- Measures of Absolution (2013)
With Ivan Brandon:
- Frontlines: Requiem (four issues, Jet City Comics, 2016)
The Palladium Wars series
- Aftershocks (July 1, 2019), ISBN 978-1-5420-4355-7, 47North
- Ballistic (July 21, 2020), ISBN 978-1-5420-9007-0, 47North
- Short fiction
- Ink and Blood (2011)
- Cake Whores of Mars (2012) 
- Kloos, Marko. "about". Retrieved 29 April 2015.
- Liptak, Andrew (31 January 2015). "Craving a new military science fiction thrillride? Pick up these books". io9. Retrieved 29 April 2015.
- Flood, Alison (17 April 2015). "Hugo award nominees withdraw amid 'Puppygate' storm". The Guardian. Retrieved 29 April 2015.
- Who Won Science Fiction’s Hugo Awards, and Why It Matters, by Amy Wallace, in Wired; published August 23, 2015; retrieved August 23, 2015
- "Forthcoming Books". Locus Online. 2017-08-29. Retrieved 2018-12-10.
- Liptak, Andrew (30 April 2016). "Marko Kloos On Turning His Military Service Into Kickass Space Adventures". io9. Retrieved 30 April 2016.
- "Marko Kloos". Beneath Ceaseless Skies. Retrieved 29 April 2015.
- "Aftershocks (The Palladium Wars)". Amazon.com. 2019-07-07. Retrieved 2019-07-07.
- "Ballistic (The Palladium Wars)". Amazon.com. 2019-07-07. Retrieved 2019-07-07.
- "a first day of fall freebie: cake whores of mars". 23 September 2015.