Maritime New Zealand has said it was generally men who died on the water and a culture change was needed.
The organisation said was frustrated with this year's boating toll, which stands at 26.
Two men drowned yesterday when their boat capsized while crossing the Manukau Harbour Bar.
The police have named them as Terangi Woonton, 59, and Kairangi Samuela, 53. Another three people were injured and taken to hospital.
Maritime New Zealand said deaths from boating accidents are at a ten-year high - last year 19 people died.
The organisation's deputy director Lindsay Sturt said it was trying very hard to get basic safety messages across to boaties.
But Mr Sturt said men in particular tend to be over-confident and underestimate the risks. He said those two factors are behind most drownings.
Mr Sturt said New Zealand has managed to change its culture towards wearing seatbelts and the same thing needs to happen for boat safety.
Coastguard warns boaties about Manukau bar
The New Zealand Coastguard president Dean Lawrence said boaties in Auckland must make sure they can cross the Manukau Harbour Bar safely, before attempting to get through the treacherous stretch of water.
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Mr Lawrence said boaties in Auckland must make sure they can cross it safely, and that their boat is capable of doing it.
Mr Lawrence, who was also a skipper at the Waiuku Coastguard, said the bar was a short patch of water where the harbour emptied out into the sea, and when the wind was against the tide, it could cause waves to stand up, making it dangerous.
He said if boaties were going to cross it, they should know where the channels are, the time of tides, and whether their boats could stand it.
Mr Lawrence said the Waiuku Coastguard runs education days about crossing the bar.
Mr Sturt said the boat death toll was disappointing, especially given the effort the Safer Boating Forum had put in to make people aware of boating safety.
"It's extremely disappointing - most of these accidents are avoidable, if people follow a few basic safety rules - simple things like wearing your life jacket - in fact two-thirds of fatalities could be avoided if people wore their lifejackets," he said.
Mr Sturt said it was also important to have some form of communication on board, such as a cellphone in a plastic bag.
He said boaties should also check the weather and tides before they go out.
Rescuers saved three lives, say police
Police say the heroic actions of members of the public saved the lives of the three men.
A passing boat rescued the three survivors and took them to shore.
It also collected the bodies of the two victims.
Detective Sergeant Alisse Robertson said the actions of the rescuers were heroic and there was no doubt they saved three lives.
She said the five men on the capsized boat were all wearing life jackets but crossing the bar can be dangerous.