Pauline Hanson has condemned the behaviour of an apparent One Nation supporter after a racist note was allegedly left on the windscreen of an Indigenous woman's car near a Brisbane shopping complex.

Copies of a handwritten letter about an alleged incident at Chermside have been circulating on Facebook and Twitter since late Thursday night.

It's believed the original post came from a closed Facebook group; however ABC has been told by an administrator of the group that the post has since been removed.

The ABC has attempted to contact the original poster.

The handwritten note stated:

"I'm writting [sic] this note because I hit your car! You have an Aboriginal sticker on your car so the Goverment [sic] probs paid for it out of my taxes. HAPPY AUSTRALIA DAY. I'm not sorry as well. 2019 ONE NATION

Ms Hanson responded to the incident via Facebook, saying it was "not acceptable".

"Let me just say to the person who thought it was acceptable to write this unsympathetic and spiteful note, you need a good lesson on what I stand for," Ms Hanson said.

"I don't care if you're white, black or brindle — I have always called for the equal treatment of all Australians.

"What you should have done was take responsibility for your amateur driving and left a note with your full details and perhaps a sincere apology.

"I know Chermside have a significant number of security cameras, so I hope they have your actions on camera."