Evidence for the world’s earliest stone tools dates to 3.4 million years ago and pre-dates the earliest known Homo species in eastern Africa. However ground-edged tools did not appear until the dispersal of cognitively fully modern Homo sapiens sapiens out of Africa. We report on the discovery of the earliest securely dated ground-edge implement in the world at Nawarla Gabarnmang (northern Australia). The fragment of ground-edge axe is sandwiched between four statistically indistinguishable AMS radiocarbon dates of 35,400±410 cal BP, indicating technological innovations by fully modern Homo sapiens sapiens at the eastern end of the Out-of-Africa 2 Southern Arc dispersal route.