Fisheries officers pulled the three survivors from the water after the fishing vessel overturned near Little Port, just outside the Bay of Islands. The fourth fisherman was found dead.
Maj. Martel Thompson of the Halifax-based Joint Rescue Co-ordination Centre said one of the men was found nearly three kilometres away from where their boat was found.
"The third survivor — he did not have a life-jacket on and was able to cling to two jerry cans," Thompson told CBC News.
"My understanding is that he was in difficult shape when we came upon him and, you know, they certainly saved his life."
A fisheries patrol vessel was in the area of Little Port when its crew spotted the overturned boat and people in the water.
The patrol officers found two of the survivors as well as the deceased man, and then learned that the last crew member was missing.
"Upon rescuing those two survivors, they learned that there was a third survivor who was believed to be alive and was still in the water," he said.
The vessel is believed to have flipped over when the fishermen were hauling in a crab pot that had become snared on the bottom. The Coast Guard vessel Cape Fox towed it into port.
The survivors were taken to hospital.