Malcolm Locke was taking a dip in Lake Diana, near his grandmother's house just north of Orlando, when he spotted the alligator's tail.
"It was coming right at me," he said. The boy tried to swim away but the reptile pulled him under the water. "It took a bite out of my head and a big chunk out of my ear."
With desperate moments calling for desperate measures Malcolm took advantage of one of the few options open to him - he punched the alligator on the snout. "It just squirmed away," he said. A neighbour drove him to a hospital.
A trapper was sent to the lake to remove the creature.
The boy's mother, Misty Warren, said the family had seen alligators in the area before, but none had ever bothered them.
The best thing to do during an alligator attack is struggle, make noise and create confusion, according to Joy Hill, a spokeswoman for the Florida Fish and Wildlife Conservation Commission. "Malcolm did the right thing," she said. "He fought the alligator and it let him go."
Such attacks are rare in Florida, with 333 recorded since 1948. Of those, only 13 have been fatal, according to Ms Hill. "Although some may be serious, in most cases people are able to fend [the alligators] off," she said.
Malcolm's family, who call him Jamie, seem to be more amazed at his response than the attack itself. "You would imagine a kid who's aggressive or outgoing punching a gator, but not someone as shy as Jamie is," his grandmother, Linda Schlapper, told the Orlando Sentinel.