In China, Xinhua reported that the National Meteorological Center had issued a red typhoon warning - the highest alert in its four-colour typhoon warning system.
More than 13,000 people were evacuated from the major tourist resort of Sanya on Hainan.
More than 200 flights at Hainan's airports have been cancelled or delayed.
The typhoon passed by the south-western tip of Hainan as it headed for landfall on the Vietnam coast close to the China border, the Hong Kong Observatory's typhoon tracker showed.
Xinhua also said that eight people had died after being swept out to sea in northern Taiwan by waves attributed to Haiyan.
The typhoon killed up to 10,000 people in one area of the Philippines alone, with rescuers as yet unable to reach many other cut-off regions.
It brought sustained winds of 235km/h (147mph), with gusts of 275 km/h (170 mph), with waves as high as 15m (45ft), bringing up to 400mm (15.75 inches) of rain in places.