Shaun Harrington, 27, told Australian Channel 9 News' "Today" show he climbed into the small bird cage so he and his twin brother, Dean, could film an "extreme cage diving" video off the Gold Coast, near Snapper Rocks.
Harrington said he knew there was a 7.8-foot shark swimming nearby, but he hadn't expected the marine creature to "come at" him.
"I just thought, 'I gotta get out of here,'" Harrington said. "I saw the shark coming and threw the budgie cage in front of it and it just bounced off it."
"I thought I would just jump in, get a couple of shots and hop out but the thing just went crazy," he said. "It wigged out and came at me. It's probably one of the dumbest things I've ever done."
Harrington said he was not injured, but he said the plan "was not the smartest thing" and there were consequences to his actions when his wife found out about the stunt.
"I'm pretty much in the dog house," Harrington said. "I'm thinking of renovating the dog house at the moment and putting a pool table in there."