The child, now nine, who cannot be named for legal reasons, was bitten on his right side causing nine punctures, by a pit bull terrier called Duke.
The attack on him happened only a few months after the child's father was bitten by the same dog, Glasgow Sheriff Court heard.
After the schoolboy was injured, at a house in Baillieston, his dad reported the incidents to the police.
Edward Heron, from Baillieston, admitted having a dog that was dangerously out of control and that bit the child on May 4, 2013 and his dad on a date in February last year.
A motion for the dog to be destroyed was granted by Sheriff John McCormack. Sentence was deferred on Heron until later this month.