The Reserve Bank of Australia's index of commodity prices in special drawing rights terms fell 5.1 per cent in October, preliminary estimates from the central bank show.
This follows an upwardly revised rise of 0.7 per cent in September.
The largest contributors to the fall in October were decreases in the prices of copper, wheat, nickel and aluminium.
In Australian dollar terms, the index rose by 9.5 per cent in October, following an upwardly revised increase of 6.4 per cent in September.
