"The market is taking some weak overnight leads and we are really going into an important jobs number that comes out of the US tonight, all eyes are focused on the composition of that jobs number and the actual headline rate," said Peter Esho, chief market analyst at City Index.
Analysts recommended adopting a cautiously bearish stance, as the market awaits the US data due at 1230 GMT.
The benchmark S&P/ASX 200 index was down 75.37 points at 4223.1 by 0200 GMT. It rose 0.3 percent on Thursday.
New Zealand's benchmark NZX 50 index fell 0.77 percent to 3,306.38.
Australian Prime Minister Julia Gillard denied she would step down after newspapers reported senior figures within her government felt she had lost her authority after the government's asylum-seeker policy was blocked by the high court this week.
If a change in Prime Minister were to occur, companies exposed by Gillard's planned carbon tax could benefit.
"If that was to occur, I think the two most obvious exposures are One Steel and Bluescope because if there is a carbon tax they are highly exposed to that regime," Esho said.
On a technical basis, the ASX 200 index appears to have completed a rally from the August low of 3,766, said Reuters Foreign Exchange Analyst, Krishna Kumar.
He said the market appear to have failed slightly ahead of the 50 percent retracement of the April-August decline( 4,371) with the move to 4,355 on Thursday, he added.
Rural services group Elders bucked the trend, rising 13 percent to A$0.345 after it secured early refinancing of its core debt facilities. STOCKS ON THE MOVE
Global miners BHP Billiton and Rio Tinto fell on softer commodity prices overnight, down 2.13 percent and 1.56 percent respectively.
0243 GMT
The big four banks also fell, ANZ bank fell 2 percent to A$19.85, Commonwealth Bank fell 1.56 percent to A$47.33, NAB was down 1.89 percent to A$23.4 and Westpac was down 1.54 percent to A$20.40.
0248 GMT
Building product manufacturer CSR Ltd fell 4.45 percent to A$2.36 in early trade after it announced on Thursday, plans to shut down some production lines at its Viridian glass business.
Qantas airways rose 2.19 percent to A$1.630 after reporting improving passenger yields.
Construction firm Leighton Holdings fell 3.55 percent to A$19.820 on reports a shareholder class action could be launched against the company, alleging it didn't properly inform shareholders about its financial performance.
Copyright Reuters, 2011