The Ontario Provincial Police say the attack happened after the 53-year-old Peterborough, Ont., woman and her dogs came across a group of three bears on a trail near 7th Line, south of Highway 7, about two hours east of Toronto.
One of the bears became aggressive and then began “biting and mauling” the woman, police say.
The woman's dogs were injured in the melee, but managed to scare the bears away.
The victim was able to get away and call for help from a local residence.
Police say she was later taken to hospital. The injuries she suffered were not life threatening.
The bears have yet to be located. Police say they have notified area residents about the incident.