The benchmark S&P/ASX200 index on Tuesday fell 28.5 points, or 0.35 per cent, to 8,176.9, while the broader All Ordinaries fell 35.3 points, or 0.42 per cent, to 8,443.7.
The ASX200 had been basically flat around midday but dropped into the red after China's state planners finally unveiled plans to bolster the world's second-biggest economy in a highly anticipated press conference.
But the National Development and Reform Commission's announcement didn't include any new measures beyond those unveiled last Tuesday, and even made it clear that the 100 billion yuan ($A21 billion) support package unveiled last week would be deducted from next year's budget.
"The market really expected more," said Alicia Garcia-Herrero, chief economist for the Asia Pacific region at investment bank Natixis, told the BBC. "I would not have organised a press conference not to announce anything new."
Chinese markets dropped, as did the ASX's iron ore giants, which sell mostly to Chinese steelmakers. The Aussie fell from 67.60 US cents to 67.18 US cents in the space of 10 minutes.
Closer to home, the Reserve Bank unveiled minutes from its September 23-24 meeting, where it kept rates on hold at 4.35 per cent.
But NAB's head of market economics, Tapas Strickland, said the minutes contained little new information on top of governor Michele Bullock's press conference.
Overall the minutes were consistent with NAB's recently revised view that the RBA would begin cutting rates in February, Mr Strickland said.
Traders were also digesting an overnight jump in oil prices, with Brent crude rising to a six-week high of $US81 a barrel after Hezbollah fired more rockets at Israel, which seemed prepared to launch major new offensives in both northern Gaza and Lebanon.
Seven of the ASX's 11 sectors lost ground on Tuesday, with health care, financials, utilities and property higher.
Materials/mining was the biggest mover, dropping 1.8 per cent on the China news.
Fortescue fell 5.3 per cent to a two-week low of $19.27, BHP dropped 2.4 per cent to $43.79 and Rio Tinto dipped 0.2 per cent to $120.99.
West African Resources made up a bit of Monday's nearly 20 per cent plunge with a 7.5 per cent rebound, after the goldminer said authorities in Burkina Faso had assured it that its mining permits there were in good standing.
The Ministry of Mines and Quarries said that junta leader Ibrahim Traoré's comments about revoking permits only applied to companies violating the law, the goldminer said.
In the energy sector, Woodside dropped 1.3 per cent and Santos dipped 0.6 per cent despite the jump in oil prices.
The big four banks meanwhile had begun the day mostly lower but closed higher, a possible indication that traders were once again selling one for the other.
ANZ, Westpac and NAB all rose 0.4 per cent, to $30.11, $30.91 and $37.27, respectively. CBA advanced 0.2 per cent to $134.97.
The Australian dollar was buying 67.25 US cents, from 67.99 US cents at Monday's ASX close.
ON THE ASX:
* The benchmark S&P/ASX200 index finished Tuesday down 28.5 points, or 0.35 per cent, at 8,176.9
* The All Ordinaries dropped 35.3 points, or 0.42 per cent, at 8,443.7
CURRENCY SNAPSHOT:
One Australian dollar buys:
* 67.25 US cents, from 67.99 US cents at Monday's ASX close
* 99.53 Japanese yen, from 100.97 yen
* 61.23 euro cents, from 62.01 euro cents
* 51.39 British pence, from 51.86 pence
* 109.93 NZ cents, from 110.41 NZ cents