Among the dead were 17 victims from Quang Ninh province, the Central Committee for Flood and Storm Control said.
The province has received more than 800 millimetres of rain in the past seven days, the most in the past 40 years.
Nearly 2,500 hectares of rice were submerged while more than 11,500 head of cattle and poultry were killed.
Total damage was estimated at about 100 million dollars, of which Vietnam National Coal and Mineral Industries Group lost 57 million dollars, the authorities said.
Electricity of Vietnam has warned of a possible shortage of power, as coal mining and transportation have been halted due to torrential rains and floods, the Viet Nam News reported.