Storm made landfall with winds of up to 90km/h, the latest in a series that have pummelled Vietnam over the past six weeks.
Storm Vamco has barrelled into Vietnam, damaging buildings and injuring at least five people after wreaking devastation in the Philippines.
The storm made landfall on Sunday with winds of up to 90 kilometres per hour (56 mph), according to media reports, uprooting trees and blowing the roofs off houses and schools.
Vamco is the latest in a series of storms that have pummelled Vietnam over the past six weeks, causing flooding and landslides that have killed at least 159 people while 70 others have gone missing.
Initial reports from the Disaster Management Authority on Sunday said five people had been injured while they were trying to secure their houses.
Vamco has weakened since hitting the Philippines as a typhoon, with winds of up to 155km/h (100 mph), but state media said it still caused significant damage, though details were not immediately available.
Authorities evacuated nearly 650,000 people from seven coastal provinces to higher and safer ground before the storm hit to try to reduce casualties.
Agriculture and Rural Development Minister Nguyen Xuan Cuong told the VNExpress news website he hoped the precautions would minimise the storm’s impact.
Damage from Vamco was severe in the Philippines, the storm causing flooding that affected more than 340,000 people.
Philippine authorities said Sunday the death toll had risen to 67, though floodwaters are now receding, giving hope the worst could be over.
In Vietnam, weeks of severe weather have damaged or destroyed more than 400,000 homes, according to the International Federation of Red Cross and Red Crescent Societies.
Roads and bridges have been washed away, power supplies disrupted, and crucial food crops destroyed, leaving at least 150,000 people at immediate risk of food shortages.