At 12pm (AEDT), the benchmark S&P/ASX200 index was up 23.3 points, or 0.68 per cent, at 3,451.9, while the broader All Ordinaries index rose 19.9 points, or 0.59 per cent, to 3392.5.
On the Sydney Futures Exchange, the March share price index contract was 37 points higher at 3409 on a volume of 11,023 contracts.
CMC Markets analyst David Taylor said Chinese demand for steel had boosted optimism heading into the weekend.
"We had a good lead from Wall Street overnight,'' he said.
"The miners are obviously gaining from positive sentiment in the market this morning. The mood's pretty good leading into the weekend.
"There's a bit of optimism around town that China may be picking their stockpiles back up and shipping may be increasing.''
By 1202 AEDT, BHP Billiton, the largest company on the Australian Securities Exchange, gained 31 cents to $31.93, while rival Rio Tinto lost 61 cents to $46.79.
Fortescue metals added nine cents, or 4.09 per cent, to $2.29 a share.
National Australia Bank reported its first quarter 2009 cash earnings will be around $1.1 billion after a deterioration in economic conditions saw bad and doubtful debts reach $824 million.
Its shares shed 24 cents, or 1.29 per cent, cents to $18.40.
ANZ Banking Group said its first half 2009 profit after credit risk on derivatives and credit provisions will be 15 per cent lower than for the first half 2008.
Its stock lifted 18 cents, or 1.46 per cent, to $12.52.
Commonwealth Bank of Australia added 31 cents, or 1.07 per cent, to $29.29 and Westpac rose seven cents to $16.09.
Macy’s to cut 7,000 jobs as consumer spending falls
Large banks take beating on Wall Street
Share market slightly lower at noon
