Charles Pickering, 69, from Driffield, had not contacted his family since 4 July.
His yacht, Equinox, which is based in Scarborough, left Kiel in northern Germany last week, heading for the UK.
Humber Coastguard said he had been found 80 miles off Spurn Point after he set off an emergency positioning beacon from onboard his 17ft (5m) yacht.
Mr Pickering's family reported him missing on Thursday after he failed to contact them.
A police investigation found he had not used his bank cards since 3 July, said Humber Coastguard.
A huge search operation, involving a rescue helicopter from RAF Leconfield, scoured the area from Scarborough to the median line in the middle of the North Sea.
Coastguards in Germany also carried out a similar search from Helgoland, a small island in the North Sea, and French, Belgian and Dutch authorities were alerted to his disappearance.
An appeal to all vessels in the North Sea was put out before the shipping forecast on BBC Radio 4 earlier.
People were asked to look out for the yacht, and the skipper was urged to make contact with the coastguard.
Mike Green, watch manager at Humber Coastguard, said: "We are all absolutely delighted that this gentleman has been found alive and well.
"It is important that yachtsmen planning this sort of passage have adequate communications and log a passage plan with a shore contact."
A lone yachtsman from East Yorkshire who went missing in the North Sea has been found alive and well.