Stimson's python (Antaresia stimsoni) is a small nocturnal python (Pythonidae) that occurs throughout Australia's arid zone. Despite its wide distribution and localised abundance, no field-based studies have been undertaken on this species. We investigated activity patterns, habitat use, diet, and body sizes of A. stimsoni in the MacDonnell Ranges bioregion of the Northern Territory. Data were collected at night by road-cruising along a sealed road transect over 12 consecutive months. We found that the species copes with the extreme weather variability of arid Australia by remaining active over a broad range of air temperatures and maximising activity following rainfall when relative humidity is high and ground-dwelling frogs, a significant prey source, are likely to be abundant. A. stimsoni ceased activity only during the coldest months of the year. The species occurs in a range of vegetation types, with an apparent preference for riparian woodland, and its ability to thrive in the MacDonnell Ranges may be related to the abundance of rock-outcrops for refuge. Our results for diet and body size support previous research based on museum specimens, confirming that A. stimsoni feeds on a range of terrestrial vertebrates and is not sexually dimorphic.