The Australian Bureau of Statistics said a 23 percent spike in the value of iron and copper ore exports and a 15 percent rise for coal, mainly due to volume increases, were behind the unprecedented performance, which was double forecasts.
The record monthly surplus takes the trade balance from a deficit of 3.29 billion in the three months to March to a surplus of 6.63 billion for the June quarter.
Commodity exports to Asia helped Australia emerge from the global downturn as the only advanced economy to avoid recession. Its trade balance returned to surplus in April after 13 months in the red.
Price gains flowing from the scrapping of annual contracts for iron ore and coal in favour of quarterly negotiations in March were credited with reversing the deficit.
Surging commodity prices are expected to drive Australia's terms of trade for 2010 to their highest level in 60 years, according to the May budget outlook, injecting 30 billion dollars (27 billion US) into the economy.