A St John spokesman said the man's companions supported him, partly on the rocks and partly in the water, until help came.
First to arrive was the Kerikeri Fire Brigade with several firefighters getting into the cold water to hold the injured man out of it.
He could be reached only by swimming across the pool at the bottom of the falls.
Police, St John Ambulance and Far North Search and Rescue volunteers were also called out.
A St John medic joined the other rescuers in the water to check the man's condition and apply first aid.
Due to the difficult access the Northland Rescue Helicopter was also called out.
The man was placed in a stretcher basket and winched into the helicopter as it hovered above the falls.
The man was flown to Whangārei Hospital in a serious but not life-threatening condition.
He was also suffering mild hypothermia after spending almost 90 minutes in the water.
The spokesman said it was a great example of different agencies working together to carry out a rescue.