Dutchman Hans Horrevoets, 32, failed to regain consciousness after being pulled from the sea by fellow crew members on ABN Amro Two.
Horrevoets had been trimming the spinnaker as the boat sailed downwind in 30 knots of wind, around 1,300 miles west of Land’s End, Cornwall.
At 2:11am a wave washed down the boat and, when the water cleared, Horrevoets was no longer on deck.
Skipper Sebastien Josse called “man overboard”. The sails were dropped and the boat motored back through a powerful head-wind to locate Horrevoets.
Crew medics attempted to resuscitate him but eventually called a halt to CPR at 4:20am.
“We are all devastated by the events that took place this morning and all our thoughts are for Hans’ family,” said Josse.
“It is with deep regret that we were unable to resuscitate Hans.”
Horrevoets was the oldest member of the ABN Amro Two crew and leaves his partner Petra with one daughter.
Originally only a member of the selection panel, Horrevoets joinedthe team after two crew members withdrew.
He was on board as ABN Amro Two broke the world 24-hour speed record during leg two of the race, when they covered 563 miles in 24 hours en route from Cape Town to Melbourne.
ABN Amro Two, currently fifth in the overall standings, were racing from New York to Portsmouth on leg seven of the voyage when tragedy struck.
The boat is back under sail again and making its way towards Portsmouth, where a decision will be made onthe team’s further participation in the race.
Volvo Ocean Race chief executive Glenn Bourke said: “When an accident like this occurs it is a shock to everyone associated with the race.”