Australian television broadcast the service for Irwin, which took place at Crocoseum stadium in Queensland. The 44 year-old star was best known for his life-threatening closeness with dangerous animals.
The Australian Prime Minister, John Howard, led the tribute, saying that Irwin had taught people to love and respect all creature, great and small.
In addition to Howard, film stars Russell Crowe and Cameron Diaz attended the tribute.
Steve Irwin died after being spiked in the chest by a stingray.