The storm, which made landfall on Saturday, is the worst in decades to strike the country's southern coastal region.
Photo from video
Nearly two dozen people are also missing after Damrey barrelled into Vietnam days before the country welcomes world leaders to the APEC summit.
More than 40,000 homes were damaged as heavy rains and 130 kph winds tore through the area, leaving 27 dead and 22 reported missing, according to the disaster management office.
Coastal Khanh Hoa province was hardest hit with 16 dead and 10 injured, the government said.
More than 30,000 people, including foreign tourists, were evacuated from the area ahead of the storm.
Some 300 ships have been wrecked, according to the government, while local authorities said Phu Yen province's Tuy Hoa city had never suffered such devastation before.
There were also reports of minor damage around 500 kilometres north in Danang, the coastal city which will host the Asia-Pacific Economic Cooperation (APEC) summit next weekend.
Strong winds and rain had torn down signs promoting the APEC gathering, which will bring together leaders including US President Donald Trump and China's Xi Jinping.
