The Fawn Antechinus is a nocturnal, generalist predator of invertebrates and small vertebrates.  It is partly arboreal. It occurs mostly in open forests and woodlands dominated by Darwin Woollybutt Eucalyptus miniata and/or Darwin Stringybark E. tetrodonta, particularly where these forests have a relatively dense shrubby understorey (Friend 1985; Friend and Taylor 1985). Such vegetation structure is typical of a regime with a low frequency or intensity of fires, and the Fawn Antechinus declines in areas with frequent intense fire (Corbett et al. 2003); however, it is not especially common in areas from which fire has been excluded for long periods (>20 years) (Woinarski et al. 2004). Breeding is seasonal, with young born in September and October; typically, litter size is ten (Friend 1985, Baker and Van Dyck 2013). There is synchronous male die-off after mating, but some females survive to a second and rarely third breeding season (Calaby and Taylor 1981, Friend 1985).

This species is endemic to Australia, where it is distributed in the tropical monsoonal part of the Northern Territory (Watson and Calaby 2008). It is present in Kakadu National Park and Litchfield National Park. With the exception of one individual reported in a brief sampling event on Melville Island (Horner and Griffiths 1998), it has not been recorded on any islands, notwithstanding much recent survey effort on islands of northern Australia, including a far more extensive and intensive sampling on Melville Island (e.g. Woinarski et al. 1999, 2011; Firth et al. 2006). The mainland limits of its range are poorly defined. A series of recent surveys has failed to record it across central and eastern Arnhem Land (Gambold et al. 1995, Brennan et al. 2003, Woinarski et al. 2008), where it was reported in the 1930s and 1940s (Johnson 1964, Dixon and Huxley 1985).

The species is present in several protected areas (e.g., Kakadu National Park and Litchfield National Park). Further studies are needed into possible threats (response to fire and toads) to the species. Monitoring is needed, along with increased management of the area.