Senior Sergeant Lucas Young of Gold Coast Water Police said the woman had confirmed a black jacket found yesterday was hers, and was on the boat at the time.
The couple did not have time to grab lifejackets or a distress beacon when two large waves hit their boat, the second one causing it to take on water and quickly sink.
Young told reporters police were hopeful of finding the man.
"The wind has dropped out, there's not a big swell out there. In these conditions, this gentleman has had experience fishing offshore on the Gold Coast so I can't see any issues there."
He said visibility from the air was good.
There are no suggestions the man had been drinking.
Young said the woman's efforts were extraordinary.
"She was very fatigued and struggled up the beach over a period of half an hour just to raise the alarm."
The woman was suffering from mild hypothermia and shock, and is recovering in Gold Coast Hospital.
Helicopters, jetskis, boats and shoreline searchers are scouring the coast.
Last night they had yet to find the boat.
- AAP
