Benny Collins, 40, a physiotherapist at Morriston Hospital's A&E department, was pulled from the sea at Three Cliffs Bay on Tuesday afternoon.
He was flown to hospital where colleagues tried in vain to save him.
His wife Mel said: "Benny was such a kind and lovely man and was loved by everyone who knew him."
The couple's nine-year-old son was also taken to hospital, but was later released.
Mrs Collins, a senior nurse at Morriston Hospital, said: "Benny was a fantastic husband and devoted father to our wonderful son. Words cannot express our feelings at this sad time.
"Benny was such a kind and lovely man and was loved by everyone who knew him. All of his family in Athea, County Limerick, loved Benny and were so proud of him."
In a statement released after his death, Abertawe Bro Morgannwg health board described Mr Collins as "a very popular, gifted and much-loved member of staff".
The wife of a man who died after getting into difficulty while in the sea off Gower has described him as a "wonderful husband".