She found the roo in the yard of her home at Bargara near Bundaberg in the Wide Bay region on Thursday morning.
"We didn't really want it coming in here because we thought if it got in here, it could do a heck of a lot of damage," she told 7NEWS.
"I was just following it around the back and was just going to chase it, hopefully, all the way around and try and get it out.
"It ended up coming inside the windbreak and it saw all the food and it started eating."
Brown said she confronted it before "it just turned on me".
"I just went to chase it away. I just went 'shoo' and it stood up and started hitting at me," she said.
"It didn't want to leave. It had the food here and it just became really aggressive.
"As soon as it started hissing, I kind of knew I was in trouble."
She said it punched her, knocking her to the ground before clawing and stomping her.
"I actually thought that was the end of me," she said.
"You hear all the stories of them disembowelling people - I was on the ground looking up at this thing, it was about my height.
"It was absolutely terrifying."
The roo began to back off when Brown's husband came to her aid, she said.
She said the attack lasted 30 seconds but left her with cuts, including one on her arm requiring stitches.
She is sporting a cast for her broken wrist.