The unidentified victim was approaching the credit union where she worked Monday, the Winnipeg Free Press reported. The six girls had been following her closely and demanded her purse, police said.
The woman resisted and one of the girls produced a hatchet and hit the woman on the head. At least four people who saw the scuffle intervened, the report said.
The girls were restrained and police later charged them with numerous offenses.
The victim was conscious and waving to coworkers as she was placed in the ambulance, one witness told the newspaper.
She was listed in stable condition Tuesday, the report said.