Northern Vietnam has entered its rainy season, with heavy downpours and flooding making travel along mountain roads treacherous.
The landslide hit the 16-seater van around 4am local time as it drove through Bac Me district in Ha Giang province, state media said.
Rescuers had recovered seven bodies, including a boy.
Six others were found alive and taken to a nearby hospital, state media said, adding rescuers were searching for those missing.
Photos and videos on state media showed excavators, ambulances and hundreds of rescue workers at the muddy hillside road.
Reports said three people travelling in a separate vehicle had been at the site when the landslide hit, but their fate was unclear.
MNA/PR