Lekima made landfall in Ha Tinh and Quang Binh provinces late on Wednesday, according to local media, and destroyed thousands of hectares of rice crops in Nghe Dien.
It was downgraded to a tropical storm after reaching Laos early on Thursday.
The Voice of Vietnam radio station said the full extent of the damage was not yet known.
Toll expected to rise
Vietnam's department of floods and storms control said a 13-year-old boy drowned in Quang Ngai while trying to anchor his family's boat.
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Vietnamese authorities evacuated
hundreds of thousands of people [Reuters] |
It said a man in Quang Nam province drowned when his boat capsized in a river.
Another death was reported in Quang Tri province and a person was reported missing in the northern province of Thai Binh.
"The casualties are expected to rise as losses from coastal areas which were worst hit by the typhoon have not been reported," Le Duc, a spokesman for the department, said.
The authorities evacuated about 400,000 people in several low-lying areas in the central provinces, issuing warnings about possible landslides and flash floods.
Vietnam faces up to 10 storms a year, causing millions of dollars in damage and sometimes killing hundreds of people a year.