Bruno Piche, 48, flew to to the fishing camp of his brother Richard, who watched from shore as the helicopter arrived, hoping to take photographs of the landing.
The helicopter then crashed into the frigid water.
Richard immediately climbed aboard a kayak to rescue his brother, who struggled to free himself from the downed aircraft.
"He had gone to the bottom of the water and was able to climb," Richard said, adding he was able to reach his brother about a mile from shore.
"I told him, remain calm and hold on," he said.
The two men finally reached shore and the pilot, who suffered minor injuries, was transported to hospital.
Firefighters and officers from the Sûreté du Québec were called to the scene of the accident.
"The sun blinded him," Richard said his brother told him.