Newly married Brian O’Callaghan-Westropp became separated from his wife Zoe Holohan as they tried to escape the fires in the coastal town of Mati.
The pair got married at Clonabreany House, Kells in Co Meath last Thursday before flying out to Greece on Saturday.
Ms Holohan, who works in advertising for the Sunday World, is in hospital after suffering burns to her head and hands.
In a statement, the family of Ms Holohan and Mr O’Callaghan-Westropp said: “We are deeply saddened to confirm the death of our family member, Brian O’Callaghan-Westropp.
“The families would respectfully appreciate privacy at this time as we grieve and as Zoe makes her recovery.
“Funeral arrangement will be announced at a later stage.”
Ireland’s Ambassador to Greece Orla O’Hanrahan confirmed Mr O’Callaghan-Westropp’s death.
She said her sympathies and heart went out to his family at this time.
The couple, who lived in Dublin, were travelling in a vehicle when they were forced to flee.
Ms Holohan was able to escape to a nearby beach and was admitted to hospital on Tuesday night.
The Irish Embassy in Athens is providing consular assistance to Ms Holohan and her family.
Mr O’Callaghan-Westropp works in finance for a Dublin catering company and also volunteers for Blood Bikes East, which provides an emergency medical transport service around hospitals in Dublin.
Committee member Franco De Bonis said Mr O’Callaghan-Westropp started off as a volunteer rider a year ago and very quickly became further involved in the service and was its secretary.
“Brian is a very charitable man - he’s one of these people who you know when he’s in the room. He has a big voice and he’s the type who wants to get things done,” Mr De Bonis said.
“He’s a man of action and is very selfless. His heart is in the right place and will always want to help.
“Brian would never walk away from a situation knowing someone needed help,” he added.
Up to 80 people have died in the forest fires which have raged through Greek villages and holiday resorts.