A 25-year-old man has died in hospital after he was pulled unconscious from the ocean over the weekend following a spearfishing accident in far north Queensland.

The man had been diving with a group of people off the coast of Hinchinbrook Island, near Mission Beach, south of Cairns, and was pulled from the water on Saturday morning by his father.

It is believed he may have suffered a blackout while underwater.

Members of the group performed CPR on the man for about 90 minutes but he did not start breathing until paramedics arrived and gave him further treatment.

He was flown by rescue chopper to the Cairns Hospital in a critical condition but died early this morning.

The ABC understands the victim was taking part in the Liam Nissen Memorial annual spearfishing event, which is held in memory of a teenager who died several years ago.

The Australian Underwater Federation's spearfishing chairman Adrian Wayne said it was a terrible tragedy.

"My heart goes out to the family and this man and to all involved in the spearfishing community," he said.

"We've had a terrible string of events in Queensland over the last 12 months."

Spearfisherman Warren Hughes was killed by a crocodile earlier this year off Innisfail.

Mr Wayne said there were concerns in the industry that people were pushing themselves too hard under the water.

"They call it shallow-water blackout," he said.

"People want to dive as deep as they can and stay as long as they can and there are lots of people around training people to do that and they can read online about how to do it."

Police are continuing to investigate the man's death and will prepare a report for the coroner.