A Perth man has been mauled by his own pet in a savage dog attack.

The bull mastiff cross only let go of the owner when people working nearby heard the 49-year-old's screams and forced it off with a shovel.

Unable to stand on his own, covered in blood and crying out for pain relief, Roy Santamaria was the victim of a brutal mauling.

View photos Roy Santamaria was the victim of a brutal mauling by his own dog. Source: 7 News More

"He had all big chunks taken out of his arm here, he had blood all over his face," friend Craig Walton said.

The 49-year-old man was trying to get his three-year-old dog, Bronx, back into the yard of his Carlisle home after he bolted outside and into a bush block next door.

Workers across the road heard the attack, ran over and hit Bronx over the head twice with a shovel.

View photos Paramedics escort Mr Santamaria to an ambulance. Source: 7 News More

The dog finally let go of his owner and ran home as Roy, in shock, loudly cursed his dog.

Unfortunately, this wasn't the first time Bronx had gone on the attack.

The dog is reportedly well-known to local council rangers.

View photos The dog, Bronx, is believed to be well-known to local rangers. Source: 7 News More

His owner was taken to Royal Perth Hospital where deep bite marks on his arms and injuries to his chest and face were treated.

The dog was taken away by the Town of Victoria Park.

View photos Clearly in pain, the dog's owner is taken to Royal Perth Hospital. Source: 7 News More

Roy's partner signed over control of Bronx to the local council, giving it authority to put him down.

However, the dog's owners have a three-day "cooling off period" to decide if they want to keep Bronx or euthanise him.

If they decide to keep Bronx, the council will hand him back.