Horrified commuters passing by can be heard yelling at the pair to stop the fight, honking their horns.
One man in an orange high-vis vest stands by and watches the altercation, making no attempt to break up the savage fight.
The video was posted to Facebook last night with the caption: "Two two sheilas having a dig on Castlereagh Rd this evening."
It has now been shared over 100 times, and has received over 1000 comments.
Another man gets out of his car and tries to intervene, yelling "stop it" and "break it up", but the two women ignore him.
No report was made to police at the time, and no current investigation is underway.
But a police spokesman told The Daily Telegraph if anyone has any information about the women involved to please contact Penrith police.
Penrith resident Khan Evan, who shot the footage, said he was shocked then the traffic came to a standstill on Castlereagh Rd.
"I have never encountered anything myself like this before," Mr Evan said. "I was being driven by my mate to an open inspection when all on a sudden the traffic came to a standstill. I said to my my mate 'what's with the traffic?" And then two females came with in view, brawling on the road."
He said people sitting in traffic watching the fight were shocked.
"Everyone was in as much disbelief as me. You just don't expect that to occur on the road way, especially from women."
