We report evidence for the world’s earliest ground-edge axe,44-49,000 years old. Its antiquity coincides with or immediately follows the arrival of humans on the Australian landmass. Ground/polished axes are not associated with the eastward dispersal of Homo sapiens across Eurasia and the discovery of axes in Australia at the point of colonisation exemplifies a diversification of technological practices that occurred as modern humans dispersed from Africa. Ground-edge axes are now known from two different colonised lands at the time humans arrived and hence we argue that these technological strategies are associated with the adaptation of economies and social practices to new environmental contexts.