Fighting back tears, the weather-beaten, khaki-clad man said that his son had been his "best mate" and funeral arrangements would be up to his widow Terri.
Bob Irwin was speaking to reporters outside his son's Australia Zoo in Queensland, where a massive shrine of flowers, notes and personal mementoes has been laid by thousands of fans of television's wildlife warrior.
The premier of northeastern Queensland state, Peter Beattie, had offered to provide a state funeral for Irwin amidst the astonishing global outpouring of grief for the ebullient star.
But Mr Irwin said his son would not have wanted a grand funeral.
"The state funeral would be refused because he's just an ordinary guy, and he wants to be remembered as an ordinary bloke," he said.
Steve Irwin, 44, was killed Monday off the Great Barrier Reef when the tail barb of a giant stingray punctured his heart as the creature lashed out at him while he was filming.
'Best mate'
Mr Irwin today described his son as his best mate.
"Steve and I weren't like father and son. We were good mates. I'm a lucky, lucky guy I've had the opportunity to have a son like Steve,” he said.
"Over the years, Steve and I have a lot of adventures together and there's been many occasions when anything could have gone wrong.
"Steve knew the risks involved with the type of work he was doing and he wouldn't have wanted it any other way. There's never been anybody else that I know of that had the personality Steve had and the strength and the conviction of what he believed in and his message was conservation.
"He was such a strong person that people all over the world believed in him."
Mr Irwin thanked the public who have come to the zoo in their thousands to lay flowers and tributes.
He said the death was taking a huge toll on the family but his daughter-in-law Terri was holding up very well.
"It's extremely hard for Terri and the children," he said. "That's why I ask the media to please give them a break for the children's sake."