Background “Closing the Gap” is an Australian government strategy that was established to address the inequality in health and education outcomes between Indigenous and non-Indigenous Australians. Although some gains have been realised, progress has been ostensibly slow. One potential obstacle is the large number of Indigenous Australians in prison. 1 in 5 to 1 in 6 Indigenous Australian males are currently imprisoned or have previously been imprisoned. Recent work has also pointed to a widening socio-economic gap within the Indigenous population. Given the myriad social, wellbeing and environmental risk factors associated with justice-involvement, it is conceivable that incarceration may contribute to the increasing disparities found within the Indigenous population. This study aimed to explore the presence and extent of an ‘incarceration gap’ within the Indigenous population and to uncover which social factors characterise the disparity. Methods The study utilised data from the 2014-5 National Aboriginal and Torres Strait Islander Social Survey (NATSISS). A number of socio-economic, environmental and clinical factors were compared by life-time incarceration status. Chi-square tests were used to examine the association between incarceration status and each of the comparison variables. Results Disparities were observed within the Indigenous Australian population across a number of important health and socio-economic markers by incarceration status - the most pronounced being for educational obtainment, labour force participation and drug/alcohol problems. Never-incarcerated Indigenous males yielded aggregate proportions across numerous variables that approximated or matched general Australian population estimates. Conclusions There appears to be evidence for an ‘incarceration gap’ within the Indigenous Australian population. It is evident that the national ‘closing the gap’ strategy necessitates contending with Indigenous over-incarceration.