Merseyside Police said the dog was destroyed after Clifford Clarke was attacked in Richard Kelly Close, Clubmoor, at 20:40 BST on Saturday.
The women, aged 27 and 28 and from Clubmoor, were arrested after Mr Clarke was found in his garden.
A post-mortem examination of his body is taking place.
Police said the dog was out of control when officers arrived at the house and found the injured man in the garden.
Mr Clarke was later pronounced dead in hospital.  The breed of dog has not been confirmed but nearby residents said it looked like a Staffordshire Bull Terrier.
Neighbours reported screams while others thought a dog fight was taking place.
Mr Clarke, who was reportedly cooking some food prior to the attack, told neighbours his fence had been damaged by dogs.
The BBC understands neighbours had reported "out-of-control dogs" jumping over fences in the area.
The two women were originally detained under the section of the Dangerous Dogs Act that relates to an owner or a person in charge of the dog allowing it to enter a private property where it is not permitted to be and the animal injures a person.
They were later released on bail by police who have appealed for anyone with information to come forward.
Two women are being questioned on suspicion of manslaughter after a 79-year-old man was fatally injured by an "out-of-control" dog in Liverpool.