Ontario Provincial Police in Ignace reported the man was attacked Saturday afternoon.
The man was on a walk with his two dogs when he decided to take a break near the water and was attacked from behind by a mature black bear, police said.
The man got away by running into the water, where he waited until the bear eventually walked away.
He later attempted to walk back to his camp site, but the bear came back and attacked him again, police said.
One of the dogs attempted to protect its owner and fend off the bear, allowing the man to get away. He eventually made it to the park ranger station, where he was treated for non-life-threatening injuries and transported to Dryden Regional Health Center.
The bear was shot by park officials, but still has not been located.
Police have issued a warning to people in the area of Sand Bar Provincial Park to be extra vigilant and protect themselves.
Ministry of Natural Resources conservation officers, along with the K9 unit, are tracking the bear.