This study was commissioned by Geoscience Australia (GA) as part of the Resourcing Australia’s Prosperity initiative to produce a report on the organic petrology of rock samples from drill holes in the Birrindudu Basin, Northern Territory, Australia. A suite of 97 drill core samples from 5 drill holes was analysed using standard organic petrological methods to identify the types of organic matter present, assess their relative abundances and determine the levels of thermal maturity attained by the sedimentary organic matter using the reflectance of organoclasts present. The primary organic matter identified was non-fluorescing coalified alginite, likely from filamentous cyanobacteria, along with significant graphite in 10 samples from the undifferentiated basement. The graphite likely formed through contact metamorphism and tectonic shearing. Secondary organic matter included bitumen, diffused unstructured organic matter, and dead oil droplets.