The pair had climbed onto a small fishing boat for safety after their inflatable kayak capsized in Galway Bay.
A major search and rescue operation was mounted after lifeguards at Trácth beach near Kinvarra became concerned for the pair who had set off from there at around 12.30pm.
The alarm was raised at around 3.05pm when there was no sign of the pair returning.
The Galway Bay RNLI lifeboat and the Irish Coast Guard unit based at Doolin in Co Clare were alerted. The Shannon based search and rescue helicopter, Rescue 115, was also tasked to the area.
The man and his son had been thrown overboard from their kayak and had climbed aboard the boat for safety.
They were taken on board the lifeboat and back to the RNLI station in Galway. They were reported to be shaken but unharmed and not in need of medical attention.
